Chem LVL 5

"Pigs" and "castles" named for this element are often used to follow the ALARA (uh-LARR-uh) safety protocols. Double contrasting in electron microscopy uses this element's citrate in combination with uranyl acetate. Either silver or this metal is added to detect iodide in solution since it forms a yellow precipitate. Because of the inert pair effect, this element in the carbon group has a more stable plus-two oxidation state than (*) plus-four. This element is both oxidized and reduced by sulfuric acid in the oldest type of rechargeable galvanic cell. Because its 208-isotope is doubly magic, the thorium and uranium decay series both end on this element. Galena is an ore of it. For 10 points, name this toxic metal often used in radiation shielding, which has the symbol Pb.

lead [or Pb until it is read] <Silverman>

This statement is applied separately to each component in multicomponent analysis. NanoDrop devices use this law to calculate the 260/280 ratio of DNA and proteins. This law can be written as I equals I-nought times the exponential of negative alpha times density times distance. A correction factor is added to this equation if turbidity is present. A parameter in this law has units of inverse molar times inverse centimeters. A calibration curve and a (*) blank are usually used to standardize before this law is applied, often to find the optimal wavelength. The cuvette path length in this law multiplies the extinction coefficient and concentration to give absorbance. For 10 points, name this law which governs spectrophotometers.

Beer's law [or the Beer-Lambert law]

If this law holds, a Job plot can be used. This law is derived by integrating negative N times sigmaover a series of thin slices. The ratio of two values computed using this law is used to assess the purityof a DNA sample. This law can be used to extrapolate points on a Bradford assay, assuming thesample is in the linear range. This law assumes no turbidity, that the incident flux is non-invasive,and that the medium is homogenous. In one form, this law says (*) A is equal to the product of theextinction coefficient, path length, and concentration. This law can be written in terms of the transmittanceor absorbance. For 10 points, name this law is often used in spectrophotometry to measure theconcentration of a sample using monochromatic light.

Beer-Lambert-Bouguer law

This compound causes pyrogallol solution to turn colorless. Methods of measuring the amount ofthis compound in solution include adding manganese sulfate and potassium iodide in the Winklertest. Another method to measure its concentration uses a zirconia probe. Molecular orbital theory isused to explain why its triplet form is paramagnetic, and its singlet form is very reactive. Onemolecule of it is combined with sulfur dioxide in the first step of the (*) contact process, whicheventually produces sulfuric acid. Subjecting it to strong electric shocks transforms it into its triatomicform, which is called ozone. For 10 points, name this diatomic gas, which comprises 21% of Earth'satmosphere and is exchanged with CO2 in respiration.

Diatomic oxygen [or O2 ]

This scientist is the first namesake of a reaction in which Fenton’s reagent is used to generate hydroxyl radicals. C. I. Bliss proposed a more complex model to improve upon this man’s namesake rule, which states that C times t equals k. An osmium catalyst was replaced by a cheaper (*) iron catalyst in a process developed by this scientist that adds hydrogen and breaks a triple bond. This German scientist developed the idea to use chlorine gas in World War I. For 10 points, name this chemist who created a process to make ammonia that was improved by Carl Bosch.

Fritz Haber <BC>

The residual of this quantity equals RT times the log of the fugacity coefficient. This quantity isused as a generating function since its canonical variables are temperature and pressure. The changein this quantity at non-standard state equals its change at the standard state, plus RT times the log ofthe reaction quotient, which can be used to derive the Nernst equation. This extensive quantity canbe calculated by summing (*) chemical potential over particle number. The change in this quantity atstandard state equals negative RT times the log of the equilibrium constant. In general, it equals enthalpyminus temperature times entropy. For 10 points, name this quantity which determines if a process isspontaneous, named for an American chemist.

Gibbs free energy [or G; prompt on free energy]

Anesthesiologists often use a form of this equation which includes the constant 6.1, which is a certain value for H2CO3. The Charlot equation is used instead of this equation when water’s autoionization is non-negligible. An early form of this equation modeled the buffering behavior of CO2, and a logarithmic function was later added to make it compatible with Sorensen’s (*) pH terminology. This equation states that pKa plus log base ten of the concentration of A- over the concentration of HA equals pH. For 10 points, name the equation which defines pH in terms of the acid dissociation constant.

Henderson-Hasselbalch equation [generously prompt on Henderson equation] <AJ>

This chemist opened his Nobel lecture by citing Wilhelm Pfeffer's (FEFF-er’s) studies into tree sap as a key motivation. Plotting the natural log of a reaction's equilibrium constant vs. one over temperature yields a line according to this scientist's equation. A quantity named for this scientist will always be a positive integer for strong acids, strong bases, and salts, but not (*) weak acids and weak bases. That quantity, for potassium chloride and calcium chloride, equals two and three respectively, because they dissociate (diss-OH-see-ate) into two and three ions. For 10 points, identify this Dutch scientist, the namesake of a factor used to describe colligative properties and the first Nobel laureate in chemistry.

Jacobus Henricus van 't Hoff [or van 't Hoff equation; or van 't Hoff factor] <Prieto, Science - Chemistry>

For ideal solutions, a form of this statement can be derived simply by summing the Lewisâ€"Randall rule over every species. Arnold Beckman's original pH meter worked by solving this equation for proton concentration. The discoverer of this equation invented a better incandescent lamp than Thomas Edison's and won a Nobel Prize for discovering the Third Law of Thermodynamics. A variant of this equation in (*) biochemistry only considers sodium, potassium, and chlorine ions and includes a coefficient of 61.5 millivolts across the plasma membrane. This equation predicts that free energy depends on RT times the log of the reaction quotient, but first divides each term by nF to get units of volts. For 10 points, name this equation that gives the redox potential of a galvanic cell.

Nernst equation <Silverman>

One generalization of this equation can be applied across the Stern layer after applying theFrumkin correction. Combined with activities, this equation is used to derive the boundary linesfound in Pourbaix diagrams. At equilibrium, this equation can be derived by setting the reaction rateto zero in the Butler-Volmer equation. One generalization of this equation multiplies each term witha permeability and is used to find the (*) resting potential across a cell membrane. The coefficient of thisequation is RT over zF, which at 25 degrees Celsius reduces to 0.0592 over z volts. This equation is used tofind the reduction potential of a half-cell. For 10 points, name this basic equation of electrochemistry.

Nernst equation [accept Butler-Volmer equation before mention]

This equation can be obtained by removing the exponential from Margules' equation. It is derived by equating the chemical potentials of two components and rearranging until the fugacities remain. This law applies to systems for which the enthalpy of solvation is zero, and common systems used to illustrate it are mixes of isomers like 1-propanol and 2-propanol. For real systems this law usually applies to the (*)) solvent while Henry's law applies to the solute. This law applies to ideal solutions only, and positive or negative deviations from this law create difficult-to-break systems called azeotropes. For 10 points, name this law which states that the partial pressure of a component of a solution is equal to its mole fraction times its vapor pressure.

Raoult's Law

Hydrogen is represented as a circle with a dot and helium as a circle with a line in a weird notation created by this man. This man discovered that adding certain salts to water did not increase his volume, and he also independently rediscovered the Hadley cell. This man included a definition of the dew point along with the observation that rain occurs when temperature decreases in his (*) Meteorological Observations. This scientist thought that discoloration of the liquid in his eye led to his colorblindness, and he proposed an incorrect “law of greatest simplicity.†This scientist postulated that atoms combine in whole-number ratios to form compounds, and he also found that the total pressure of a mixture of gases is equal to the sum of its partial pressures. For 10 points, name this English chemist who names a law of “multiple proportions†and also pioneered the atomic theory.

John Dalton <Hao>

The Tang-Toennies model provides a damping function for this interaction. The original derivedpotential of this interaction includes a term for negative three-halves times the geometric mean oftwo ionization energies. The potential energy of this interaction is proportional to distance raised tothe negative sixth power and is negative in the Lennard-Jones potential. Its strength is roughlyproportional to the (*) polarizability. This interaction explains why bromine is liquid at room temperaturebut chlorine is a gas, because it is stronger for compounds with larger electron clouds. For 10 points, namethis interaction which forms due to induced dipoles in uncharged compounds, a class of van der Waalsforces.

London dispersion forces [or London dispersion forces; prompt on van der Waals forces before it is read]

A device named SHRIMP performs this technique using a geometry named for Matsuda consisting of quadrupole lenses and an 72.5° magnetic sector. One variant of this technique uses a Penning trap and then performs a Fourier transform to obtain the final data, and sinapinic acid is often used as a matrix material in another variant of this technique that uses a (*) laser to fragment molecules. A ketone group may undergo beta cleavage in the McLafferty rearrangement in this technique, whose “tandem†version is used to sequence proteins. The M+2 peak is one-third as high as the M peak when this technique is applied to chlorine-containing compounds. The base peak is the highest peak in the spectrum obtained from this technique. The m-to-z ratio is commonly used in reporting data from, for 10 points, what technique that gives information relating charge to its namesake property?

Mass spectrometry (or mass spectroscopy)

At the critical point, this equation predicts a compressibility of three-eights. The criticalexponents predicted by this equation are identical to those predicted by the Ising model, placing it inthe universality class of mean field theories. It is derived using the hard-sphere potential. Aroundphase transitions, it incorrectly predicts oscillatory isotherms. This equation can be derived bytruncating the virial expansion at two (*) terms. One constant in this equation accounts for the excludedvolume of a particle, and another accounts for attractive forces. It adds two constants, a and b, to a lessaccurate law. For 10 points, name this improvement on the Ideal Gas Law, named for a Dutch physicist.

Van Der Waals equation

Many versions of this technique use polarization transfer to enhance signals. Sequential walking isused to correlate cross-peaks in two-dimensional forms of it. This technique can be used instead ofX-ray diffraction on small proteins in solution. TMS is used as a standard in this technique, in whichJ-couplings split signals and the integration gives the number of equivalent atoms. This techniquerelies on the fact that atoms in different chemical environments (*) oscillate at different frequencies. Itoperates by subjecting a solution of a molecule to a series of radio frequency pulses, and a variation of itused in medicine is the MRI. For 10 points, name this type of spectroscopy that uses very high poweredmagnets to determine chemical structures.

NMR spectroscopy [or Nuclear Magnetic Resonance spectroscopy; prompt on "MRI" or "Magnetic Resonance Imaging" before mention]

An equation relating polarization resistance and corrosion current, the Stern-Geary equation, can be derived from a modification of this equation, and the Frumkin correction can be applied to that same modification of this equation. One can use the statistical definition of entropy or Boltzmann factors to derive this equation. Eta is the activation overpotential in one modification of this equation, and when it is high, that modification becomes the Tafel equation. This equation is used to draw the lines of a (*) Pourbaix diagram, and if reaction rate is 0, this equation can be derived from the Butler-Volmer equation. A factor of 61.5 is multiplied in a biochemical modification of this equation, which is the Goldman equation. RT over zF is multiplied by the natural logarithm of the reaction quotient in, for 10 points, what equation that finds the reduction potential of a half-cell?

Nernst equation <Hao>

Every species in the Irving-Williams series has this charge. The two charged species in a Daniell cell both have this charge. In acid, manganese reacts from +7 oxidation state to this oxidation state, where it is colorless. Ions with this charge must be added to coordinate DNA polymerase during (*) PCR. Water hardening agents usually have this charge. Unusually, mercury's lowest oxidation state forms a diatomic ion with this charge. In carbon monoxide, carbon's oxidation state is this value. Nickel and zinc acquire this oxidation state after they lose their 4s electrons. For 10 points, name this value, the charge normally acquired by alkaline earth metals such as magnesium and calcium.

+2 [or 2+; or positive two; prompt on two] <Silverman>

. Stryker’s reagent contains this many copper atoms, and Chevrel clusters, type two semiconductors, contain this many atoms of molybdenum. Black phosphorus is made up of rings of this many atoms, and chromium in this oxidation state is highly (*) carcinogenic. The alkane with this many carbons has 14 hydrogens. The first noble gas compound was made up of xenon and this many fluorine atoms, and p shells can hold this many electrons. Oxygen contains this many valence electrons. For 10 points, name this atomic number of carbon.

6 <BC> BONUSES

A di-iso-butyl hydride of this element is used to transform acid chlorides into aldehydes. Like iron, a Lewis acid of this element is often used in Friedel-Crafts reactions. One method for extracting this element uses an aqueous sodium hydroxide and works because this element is soluble in strong bases, but iron oxide is not. That process is supplemented by a cathodic deposition of this element through the use of (*) molten cryolite and the oxide of this element. This element is produced by the Bayer and Hall-Heroult processes. It is the most abundant metal in the Earth’s crust and extracted from bauxite. For 10 points, name this lightweight element with atomic number 13, a metal often used in soda cans.

Aluminum [or Al]

A correction to this equation includes a constant Q, a function of mass and the barrier width,when quantum tunneling is possible. The concentration of crystal defects is modelled by thisequation. A microscopic version of this equation uses a transmission coefficient, multiplied byBoltzmann's constant times temperature over Planck's constant. On a linear plot generated from thisequation, the x-axis is one over temperature, and the y-intercept is the log of the product of the (*)collision frequency and the steric factor. An increase of temperature of 10 degrees causes the left side ofthis equation to approximately double. For 10 points, name this equation which gives the reaction rateconstant as a function of temperature, named for a Swedish chemist.

Arrhenius equation

The mercuric salt of this ion is used for oxymercuration. Like borate, Tris bonds this ion in a commonbuffer for electrophoresis. This ion is the smallest short-chain fatty acid. This ion, which has a conjugatepKa of 4.76, is a much weaker base than ethoxide, as shown in a common classroom example of resonancestability. Cellulose esters are almost always made to this group, which is added to salicylic acid to make(*) aspirin. Like nitrate, chlorate, and perchlorate, all salts of this anion are water-soluble. Adding vinegar tobicarbonate makes carbonic acid and this ion. This carboxylate has two carbon atoms. For 10 points, name this ionwith formula CH3COO minus, the conjugate base of acetic acid.

acetate [or acetyl group; or acetoxy group; do not accept or prompt on "acetic acid"]

One method of producing this compound uses an iridium di-iodide di-carbonyl catalyst, whichreplaced an earlier rhodium-based catalyst. Current methods of synthesizing this compound involvethe metal-catalyzed carbonylation of methanol, which includes the aforementioned Cativa and (*)Monsanto processes. One form of this compound with no water in solution is commonly used as arecrystallization solvent; that is its "glacial" variety. It has a pKa of about 4.8 and can be synthesized bytwice oxidizing ethanol. This two-carbon molecule is one of the simplest with a carboxyl group, though ithas one more carbon than formic acid. For 10 points, name this acid with formula CH3COOH, which isfound in vinegar.

acetic acid [or acetate; accept CH3COO, CH3COO minus, or CH3COOH before the formula is read]

Four equivalents of this compound are bound to an ethylene diamine center in a famouscalcium-binding hexadentate ligand. The protecting groups in solid-phase peptide synthesis are oftenremoved using a trifluorinated derivative of this compound. One process for producing thiscompound uses a rhodium dicarbonyl diiodide catalyst; that process proceeds via carbonylation ofmethanol and is the (*) Monsanto process. An anhydrous form of this compound is commonly called"glacial." This compound can be produced by oxidizing ethanol twice, and it is the second simplestcarboxylic acid, after formic acid. For 10 points, name this acid with formula CH3COOH, which iscommonly found in vinegar.

acetic acid [or ethanoic acid, acetate; accept CH3COOH or CH3COO- before "CH3COOH"]

This element is the heaviest element found in the molecule X-gal. In mass spectrometry, the presence of this element is easily seen because of an M-plus-2 peak at the same height. This element's binary acid adds anti-Markovnikov to an alkene in the presence of peroxides. Its (*) ethidium salt intercalates DNA and fluoresces during gel electrophoresis. Diphenyl ethers with many atoms of this element attached are used as a flame retardant. Double bonds in compounds are qualitatively detected by adding this element, since the solution will turn from brown to colorless. This element of group 17 has an electron configuration ending with 4p5. For 10 points, name this halogen that presents at room temperature as a reddish brown liquid.

bromine [or Br] <Silverman>

In one kind of this technique, the graph of power versus time produces spikes that are pointed upwards if the reaction is endothermic, or downwards if exothermic. A polymer's glass transition temperature is usually detected by one of these techniques, signified by a sharp increase in heat capacity. This technique, which includes (*) differential scanning and isothermal titration types, sometimes monitors the change in temperature of a water bath modeled by the equation q equals mc delta-T. Maintaining a constant volume forces all energy to be released as heat instead of work, which is the "bomb" type of this technique. For 10 points, name this technique which measures a system's heat change.

calorimetry [or calorimeter; or differential scanning calorimetry; or isothermal titration calorimetry; or bomb calorimetry; prompt on DSC; prompt on ITC] <Prieto, Science - Chemistry>

The star R Coronae Borealis varies irregularly due to emission of clouds of this element. The atmosphere of CW Leonis is dominated by this element. In addition to transition metal oxides and lithium, compounds containing this element are characteristic of spectra of brown dwarfs. The immediate cause of type Ia supernovae is the "detonation" named for it, which occurs when core temperatures become high enough to fuse it. Hoyle predicted the existence of a resonance nuclear state of one isotope of this element that is formed by the (*) triple-alpha process. Oxygen, nitrogen, and this element are used catalytically in a namesake cycle that is the major alternative to the proton-proton chain. For 10 points, name this element which is the basis of all known forms of life.

carbon [or C; accept isotopes like (number)C or carbon-(number), where (number) is from 8 to 23 inclusive]

Hummer's method produces a material consisting of this element and oxygen, which is abbreviated GO. A similar material to that one provided experimental evidence of Berry's phase and a half-integer quantum Hall effect. Water gas is produced by passing superheated steam over this element. By blasting a disk made of it in the presence of helium, Curl, Smalley, and Kroto discovered a new molecule that weighed 720 grams per mole. Andre (*) Geim (GUY’m) received the Nobel for making monolayers of this element with scotch tape, and its atoms entirely make up a buckyball. The definition of organic chemistry requires the presence of this element in compounds. For 10 points, name this element that comprises the graphene sheets found in graphite.

carbon [or C] <Prieto, Science - Chemistry>

Chemical scrubbers and the oxides of calcium and magnesium are commonly used to remove this molecule. Along with hydrogen gas, this molecule is the end-product of the water-gas shift reaction. Antisymmetric stretching and bending are the only two observed modes of vibration in this molecule, released during the conversion of pyruvate to acetyl-CoA. This molecule dissolves in the bloodstream, resulting in a proton and a (*) bicarbonate ion, via carbonic anhydrase. The primary culprit of ocean acidification, this molecule is the simplest to have a linear arrangement about a central atom. For 10 points, name this triatomic molecule, a greenhouse gas produced alongside water in combustion reactions.

carbon dioxide [or CO2]

21. Cell culture incubators are typically named for the fact that they maintain a high pressure of this gas. The amount of this gas dissolved in a liquid is measured by titration with bromothymol blue. Synechococcus evolved microcompartments to concentrate this gas. Stromatolites likely reduced the concentration of this gas in the early atmosphere. Since addition of this gas to (*) RuBP is catalyzed by a highly inefficient enzyme, some organisms concentrate it in bundle-sheath cells. Increasing the partial pressure of this gas in the blood leads to acidosis. Yeast ferment glucose to ethanol and this gas, but in aerobic situations, a mole of it is formed per mole of pyruvate in the Krebs cycle. For 10 points, name this gas produced during cellular respiration.

carbon dioxide [or CO2] <Silverman, Science - Biology> NSC 2019 - Round 05 - Bonuses

This neutral covalent compound, with its large ligand-field splitting parameter, is located at thegreatest end of the spectrochemical series. A methyl group migrates to this compound in a criticalstep of the Monsanto process and other hydroformylations. This compound has a nearly zero bonddipole moment because its formal charges are oriented opposite the bond polarity. Water gascontains this compound and (*) hydrogen, and in the water gas shift reaction, this compound reacts withwater. It is isoelectronic to cyanide. Incomplete combustion of hydrocarbons gives water and thiscompound. The affinity of this compound for hemoglobin is much stronger than oxygen's affinity, which iswhy this gas is so toxic. For 10 points, name this compound with formula CO.

carbon monoxide [or CO before it is read]

According to the Suess effect, this substance is more concentrated in the atmosphere than in fossil fuels, and it was replaced in the urea breath test by another lighter substance. Along with positrons, this substance is created due to the interaction between cosmic rays and atmospheric (*) nitrogen. Willard Libby analyzed the concentration of this substance in the Dead Sea Scrolls. This radioactive isotope decays into nitrogen-14 and has a half-life of 5,700 years. For 10 points, name this isotope of carbon used in radiocarbon dating.

carbon-14 [accept C-14 or 14C, prompt on carbon or C] <AJ>

The position of these structures is indicated by the superscript next to the delta symbol in the IUPAC notation for fatty acids. These structures cannot exist as the bridgehead of a ring system according to Bredt's rule. An additional ghost atom is needed to deal with these structures according to the Cahn-Ingold-Prelog rules, which can also specify their geometry by marking them (*) E or Z. Nine of these structures make up a conjugated system in the central ring of chlorophyll, causing its green color. These structures contain one sigma and one pi bond, occur between sp2-hybridized carbons, and can be labeled cis or trans depending on orientation. For 10 points, name this type of bond indicated by two parallel lines which characterize alkenes.

carbon-carbon double bond [prompt on alkenes before mention; prompt on pi bonds before mention] <Mukherjee>

The Flippin-Lodge and Burgi-Dunitz angles describe nucleophilic attack on this functional group,which can be protected by converting to a 1,3-dioxylane in a reaction with ethylene glycol. Imines canbe synthesized from amines and these groups, and an alkene can be turned into two of these groupsthrough ozonolysis. Grignard reagents attack these groups to form (*) alcohols, and phosphoniumylides convert them to alkenes in the Wittig reaction. PCC and chromic acid reagents yield these groupsthrough oxidation of primary or secondary alcohols. Two of these groups are bound to the same oxygenatom in anhydrides. For 10 points, name this functional group found in amides, esters, ketones, andaldehydes, characterized by a carbon-oxygen double bond.

carbonyl group [accept aldehyde or ketone]

In the Hunsdiecker (“hoonz-DYECK-erâ€) reaction, silver salts lose this functional group and the Barbier-Wieland degradation is performed on compounds with this functional group. This functional group can be removed from a molecule via Kolbe electrolysis. This functional group differs from amides by having OH in place of NH2. Oxidation of aldehydes or (*) primary alcohols forms molecules with this functional group. Molecules with this functional group are Bronsted-Lowry acids, and examples include formic and acetic acids. For 10 points, name this organic acid functional group with formula C-O-O-H.

carboxyl group [accept COOH before read] <AJ>

According to IUPAC (I-U-pack) nomenclature rules, this functional group has ultimate priority in determining the base name of a compound. Anhydrides and nitriles are classified as derivatives of these compounds, which form when water kicks out chlorine in an acyl chloride. They also form when primary alcohols react with cold potassium permanganate. A common example of resonance is the rationale that these compounds have more stable conjugate (*) bases than alcohols. These functional groups appear at the C terminus of all proteins. These compounds, which form dimers in water, react with alcohols to form esters and form peptide bonds with amines. They have pKa values around five. For 10 points, name these compounds that have a COOH functionality, which makes them acidic.

carboxylic acids [or carboxyl group; prompt on acids] <Silverman>

This was the first compound to be found in interstellar medium using only radio interferometers; that discovery was made by David Mehringer. Ketene reacts with water to form this compound, and carbon disulfide was chlorinated in the first inorganic synthesis of this molecule, which was discovered by Hermann Kolbe. Four groups of this compound are found in a chelating agent called (*) EDTA. Solid-phase peptide synthesis often uses a trifluorinated version of this compound, and one process for producing this compound uses an iridium di-iodide dicarbonyl catalyst. That process, which proceeds by the carbonylation of methanol, is named for Cativa and replaced the earlier Monsanto process. At 16.6 degrees Celsius, the anhydrous “glacial†version of this compound begins to form. This compound is the second simplest carboxylic acid after formic acid. For 10 points, name this weak acid, which is found in vinegar.

acetic acid or ethanoic acid or CH3COOH or HC2H3O2 <Hao>

In reactions, metal aquo complexes act as these species. These species are in the numerator of alphafractions. In organic chemistry, these compounds activate electrophiles like carbonyls or alkyl halides.KHP serves this role in reactions. These compounds dehydrate sugars to pure carbon. The inductive effectexplains why nearby electronegative groups increase the (*) strength of these compounds. The "mineral" typeof these compounds are inorganic. Ammonium chloride and ferric chloride act as these species. The strength ofthese compounds varies inversely with their pKas. In reactions, they are often written as "HA." For 10 points, namethese compounds which accept electron pairs or donate protons to solution, the opposite of bases

acids [or Lewis acids; or Bronsted-Lowry acids; or Arrhenius acids; or strong acids; or weak acids; prompt on electrophiles]

In reactions, metal aquo complexes act as these species. These species are in the numerator of alphafractions. In organic chemistry, these compounds activate electrophiles like carbonyls or alkyl halides.KHP serves this role in reactions. These compounds dehydrate sugars to pure carbon. The inductive effectexplains why nearby electronegative groups increase the (*) strength of these compounds. The "mineral" typeof these compounds are inorganic. Ammonium chloride and ferric chloride act as these species. The strength ofthese compounds varies inversely with their pKas. In reactions, they are often written as "HA." For 10 points, namethese compounds which accept electron pairs or donate protons to solution, the opposite of bases.

acids [or Lewis acids; or Bronsted-Lowry acids; or Arrhenius acids; or strong acids; or weak acids; prompt on electrophiles]

For the folding of the barnase protein at room temperature, this value is negative in accordancewith the funnel model. One method of finding this value involves finding the slope of a line whenplotting the inverse temperature against the natural logarithm of k. This value can be found bylocating the saddle points on a potential energy surface. The rate constant is equal to an expressionincluding the exponential of this value divided by RT, all times the (*) pre-exponential factor, which isan expression named for Arrhenius. Catalysts accelerate reactions by lowering this value. For 10 points,name this quantity, which is the energy required to initiate a chemical reaction.

activation energy [or E-a or E-sub-a; prompt on "transition state" or "transition state energy"]

This quantity is linearly related to a type of enthalpy in the Evansâ€"Polanyi principle. A formula that models the probability of crystal defects replaces this quantity with the vacancy energy. Because deuterium lowers the zero-point energy, it increases this quantity, in the kinetic isotope effect. This quantity is replaced by "delta-G double dagger" in the governing equation for (*) transition state theory. The difference between the forward and reverse forms of this quantity equals the reaction heat. This quantity is usually experimentally calculated as negative R times the slope of a line that is formed by plotting the log of rate constant against one-over-temperature on an Arrhenius plot. Catalysts decrease this quantity. For 10 points, name this energy "hump" that a reaction must overcome.

activation energy [or free energy of activation; or activation enthalpy] <Silverman>

A class of materials that are exceptionally good at participating in this process are composed of metal ions separated by organic struts; those are called MOFs (M-O-F’s). If you replace total enzyme, rate, and concentration in the Michaelisâ€"Menten (mih-KALE-iss-MEN-ten) equation with number of empty sites, fractional coverage, and pressure, it yields an equation that describes this process. This process is modeled as a function of pressure by the (*) Langmuir (LANG-myoor) isotherm. It's not catalysis (kuh-TAL-ih-sis), but the large surface area of zeolites (ZEE-oh-lytes) and activated carbon make them well-suited for this process that can remove gas particles from the air. For 10 points, name this process in which molecules bind to a solid surface, but not into the volume of a material itself, as in absorption (AB-sorption).

adsorption [prompt on gas storage or equivalents; do not accept or prompt on "absorption"] <Silverman, Science - Chemistry>

These compounds can be transformed into alkyl chlorides using SOCl2 and pyridine through inversion of configuration. The Dess-Martin periodinane is used to gently oxidize these compounds, and reacting two equivalents of a Grignard reaction with an ester creates these compounds. This compound and a carboxylic acid are produced in the Cannizzaro (*) disproportionation, and the secondary type of these compounds can be oxidized to form ketones. These compounds show a broad peak between 3200 and 3600 wavenumbers in IR spectroscopy. Drinking the wood variety of these compounds will cause permanent blindness. For 10 points, name this class of organic compounds characterized by a hydroxyl group, whose ethyl type can be found in sake and vodka.

alcohol <Hao>

One method of calculating this quantity sets it proportional to the natural logarithm of B sub i. This quantity is not electronegativity, but it is can be approximated by the negative of the first ionization energy plus electron affinity all over two. This quantity can also be calculated by an insertion method named for Widom. Temperature, volume, and this quantity are held constant in the (*) grand canonical ensemble. Negative S dT plus V dP equals the sum of mole number times this quantity over all components of a system; that relation is the Gibbs-Duhem equation. It's not concentration, but diffusion can occur when particles move down a gradient of this quantity, which is also equal to the partial derivative of free energy with respect to particle number. For 10 points, name this quantity, which represents the change in energy when a particle is added to a system.

chemical potential <Hao>

A class of compounds named for this element consists of a combination of a group-one metal sulfate salt and this element's sulfate salt. Either silicon dioxide or this element's oxide are the most common materials used for the stationary phase in column chromatography (chrome-uh-TAH-graphy). A very strong reducing agent consists of lithium, this element and four atoms of (*) hydrogen. A mineral containing this element, three atoms of sodium and six atoms of fluorine, called cryolite (CRY-oh-light), is used as a solvent in the purification process of this element. That process reduces this element's oxide using electrolysis, and was discovered by Charles Hall and Paul Héroult (ay-ROO). For 10 points, identify this element obtained from bauxite, which has symbol Al.

aluminum [or Al until read; or lithium aluminum hydride; do not accept or prompt on "alumina"] (The lead-in refers to the alum class of compounds.) <Prieto, Science - Chemistry>

This substance was first synthesized by using the LEAR apparatus to launch particles at xenon clusters. The ALPHA project uses minimum-B traps to contain this substance. One can analyze the 1S-2S transitions in this substance's absorption spectrum to confirm the CPT theorem. One method of synthesizing this substance involved collecting radioactive sodium in a Penning trap in the ATRAP and ATHENA experiments. The fact that this substance is (*) rare in the universe is the subject of the baryon asymmetry problem. When one atom of this substance collides with a hydrogen atom, it forms two gamma rays and two pions in an annihilation reaction. For 10 points, name this atom which consists of a single positron orbiting an antiproton, the lightest element of antimatter.

antihydrogen [or h-bar; accept antimatter until "orbiting", prompt after]

A combination of two earlier models of this thing that incorporates vibration and rotation is theso-called collective model. A correction term in a formula for these things adds or subtracts a termequal to 11.18 MeV over A to the one-half for even-even and odd-odd types of them, respectively.That formula, developed by Carl Friedrich von Weizsaecker, incorporates empirical data andassumes that this thing behaves as an incompressible liquid drop, and is used to calculate the bindingenergy of these things, which is the energy needed to (*) split them into multiple parts. These things aremore stable when their constituents are present in so-called "magic numbers". Its existence was confirmedby the results of the gold foil experiment. For 10 points, what part of the atom consists of protons andneutrons?

atomic nuclei [or atomic nucleus; prompt on atoms]

Eigen and de Maeyer proposed the products of this reaction migrate away along a "wire", faster than diffusion would predict. This reaction explains why milli-Q has nonzero conductivity. This reaction forms hypervalent seven and thirteen-atom cations according to the Grotthuss mechanism. When the concentration of the reactant is 55.6 molar, the rate of this reaction is roughly one molecule per ten hours. The equilibrium constant for this reaction at 24 degrees Celsius is ten to the negative (*) fourteenth power, and is usually set equal to the product of K-sub-a and the conjugate K-sub-b. It forms hydronium and hydroxide. For 10 points, name this reaction in which two water molecules react to form positive and negative products.

autoionization of water [or the dissociation of water; or the formation of hydronium and hydroxide from water; accept H2O instead of water, H3O+ instead of hydronium, and OH- instead of hydroxide; prompt on splitting water; prompt on similar equivalents]

9. One of these species must be added catalytically, along with palladium, to couple organoboranes to alkyl halides. Catalytic amounts of these species are needed to catalyze E2 eliminations, Claisen condensations, and Williamson ether syntheses, since these compounds convert ketones to enolates and alcohols to alkoxides. In proteins, the side chains of arginine and lysine act as these species. Sterically hindered (*) nucleophiles like amines serve as these species in organic reactions due to their free nitrogens. These species solubilize phenols and carboxyl groups by donating a negative charge in the form of an electron pair, or by removing a proton. For 10 points, name these species whose common examples include sodium hydroxide and ammonia.

bases [or alkali; do not accept or prompt on "nucleophiles"] <Silverman, Science - Chemistry>

The discharge rate of these is given by Peukert's law. Solid nickel chloride and molten sodium areused in the ZEBRA form of these devices, which is also an example of the thermal form of them. Oneof these was invented by Georges Leclanche and employs a zinc "can". They can be generallyclassified into primary and storage categories, with the latter reusable. Reactants are not continuallyadded to these devices, distinguishing them from (*) fuel cells. One form of these devices see lithiumions move alternatively between the positive and negative electrodes. These devices were pioneered by theVoltaic Pile. For 10 points, name these devices that create electrical energy from chemical energy,commonly found in sizes like D and AA.

batteries [word forms ok; prompt on electrochemical cell or voltaic cell]

Because this compound has a quadrupole but no dipole moment, it forms the prototypical systemfor T-stacking in solution. In a Frost circle, this compound's HOMO has energy "alpha plus beta".This compound can be used as an entrainer to break the ethanol-water azeotrope because it forms aternary azeotrope at 64.9 degrees Celsius. This compound, which has an index of hydrogen deficiencyof (*) 4, is the main target of EAS reactions. In line notation, a circle is drawn inside of this compound toindicate resonance. A phenyl group is this compound without a hydrogen atom. Because it is planar and hassix pi electrons, it is the simplest neutral aromatic compound. For 10 points, name this compound drawn asa hexagon with three double bonds, with formula C6H6.

benzene [or C6H6 before it is read]

Iodine and Xenon lie at the base of a valley of stability in which this process does not occur. Neutron stars would degenerate in 10 minutes through this process if all electron states weren't filled in the core. This phenomenon was used to derive Fermi's Golden Rule. The NEMO-3 experiment searches for a variant of it that can only occur if the neutrino is its own antiparticle. This process uses an intermediate W boson to transform a (*) down quark into an up quark or vice versa. This phenomenon, which is responsible for changing carbon-14 to nitrogen-14 with a half-life of 5700 years, changes the atomic number by one but leaves the atomic mass constant. For 10 points, name this phenomenon in which a nucleus emits either a positron or an electron.

beta decay [accept beta-plus decay or beta-minus decay; prompt on "decay", "radioactive decay", or "nuclear decay"]

Thermal expansion occurs because models for this quantity versus separation distance are asymmetric. This quantity is approximately the height of the well of a Morse potential. For a binary acid, this quantity equals proton affinity plus electron affinity minus ionization energy. It is exactly equal to the heat of reaction for homolysis, forming radicals. Though not heat of formation, this quantity is quite low for peroxides, explaining their (*) explosiveness. The heat of reaction equals the sum over this quantity for each of the reactants minus the sum of it for the products. It varies inversely with length and directly with order. For 10 points, name this quantity, the amount of energy released when two molecular fragments link covalently.

bond energy [or bond dissociation energy; or BDE; or bond strength; prompt on stability]

Compounds of this element and silicon were first isolated by Moissan and Stock. The selectrides are reducing agents containing this element, and cluster compounds of this element adopt closo, nido, or arachno configurations based on the number of electrons in the system. Reacting a compound of this element with an alkene is a method of oxidizing the less substituted carbon in violation of Markovnikov's rule. This element's (*) triflouride is a powerful electron-deficient Lewis acid. Hydrides of this element tend to form 3 center two-electron bonds, and this element tends to violate the octet rule by having only 6 valence electrons. For 10 points, identify this element with atomic number 5 and symbol B.

boron [or B before mention]

Eleven atoms of this element, and eleven halides, are found in the strongest known single-moleculeacid. This element's allotropes form 12-atom icosahedral clusters. A compound containing only thiselement and hydrogen unusually exhibits three different bond angles and bonds of order one-half.The formation of a pi complex allows this element to add to the less substituted carbon of a doublebond. This element and (*) gallium are used to dope silicon p-type. Nearly all compounds of this elementare Lewis acidic since it violates the octet rule by only having six electrons. It's the first element with aground-state p electron. For 10 points, name this first metalloid, which has atomic number 5.

boron [or B]

This process can be combined with a DART source, and that type uses Ultramark 1621 to calibrate. During one stage of this procedure, compounds with a gamma hydrogen will rearrange to form an enol radical, and compounds can also undergo retro-Diels-Alder reactions while undergoing it. This procedure follows gas chromatography in many setups. The first stage of this procedure creates a radical cation called the (*) molecular ion, which fragments into the base peak. In this procedure, if the m-over-z ratio is odd, then the molecule usually has an odd number of nitrogen atoms. In this process, ions are deflected by an external magnetic field into the detector. For 10 points, name this method of spectrometry which measures the namesake quantity's ratio to charge.

mass spectrometry [or MS]

This quantity oddly jumps up on every other carbon atom added to a linear alkane. This value is measured in an apparatus where you view the sample in a capillary tube through a window while ramping up the voltage; it is then reported as a range to indicate sample purity. This quantity names the point at which 50 percent of a protein is denatured. This quantity is minimized for a mixture at its (*) eutectic point. It equals the enthalpy of fusion over the entropy of fusion. The change in this quantity equals molality times the cryoscopic constant. For water, this value decreases as pressure goes up, since its coexistence curve's slope is negative. Adding salt to water depresses this property. For 10 points, name this temperature at which a liquid turns solid.

melting point[or freezing point; or melting temperature; or freezing temperature] <Silverman>

The fulminate of this element is often used as a friction-sensitive explosive in percussion caps. Minamata disease is caused by a compound containing this element bound to a methyl group, and this element’s chloride is used as a catalyst to produce vinyl chloride from acetylene. Potassium, iodine, and this element are found in a compound that turns yellow when exposed to ammonia; that reagent is named after (*) Nessler. This element is found at the bottom of the apparatus used in the Castner-Kellner process, and a dimethyl compound containing this element killed Karen Wetterhahn when it seeped through her glove. The alternative name for thiols indicates their affinity for this element, and the red pigment cinnabar contains this element bound to sulfur. For 10 points, name this element, which can be found in thermometers, with symbol Hg.

mercury (or Hg before end) <Hao> BONUSES

From classical times through the 19th century, the main source of this substance in Europe wasAlmaden in Spain. This substance is at the bottom of cells in which the Castner-Kellner process isperformed, in which it serves as a cathode. This substance was used along with saltwater in vats for the"patio process" to extract silver ores at sites in New Spain such as Potosi. A bond between it and sulfurexists in each molecule of the preservative (*) thimerosal, and it also exists bonded to sulfur in the ore cinnabar.Qin Shi Huangdi allegedly died by taking pills of this substance to extend his lifespan. For 10 points, name thismetal, the only one which is liquid at room temperature.

mercury [or Hg; or quicksilver; prompt on amalgam]

An enzyme that oxidizes this compound switches between particulate and soluble forms based on the presence of copper and is this compound's namesake "mono-oxygenase." This molecule is produced when coenzyme B reacts with a modified version of coenzyme M. Frank Keppler controversially proposed that plants directly emit this molecule into the atmosphere to contribute to the greenhouse effect. Members of a group of archaea named for producing this gas are commonly found in (*) wetlands. This compound, which is formed by the reduction of carbon dioxide, is the principal component of biogas. This compound significantly contributes to greenhouse gas emissions from livestock. For 10 points, name this simplest hydrocarbon with formula CH4.

methane [accept CH4 until read] <Ramaswami, Science - Biology> NSC 2018 - Round 24 - Bonuses

This compound has two ESCA peaks, at 14.2 and 22.9 electron-volts, which valence bond theory cannotpredict. This is the simplest compound whose bond angles exactly equal the arccosine of negative onethird.Bacteria can metabolize glucose to three molecules of carbon dioxide and three molecules of thiscompound. It reacts with water during steam reforming to make syngas, and it is triply chlorinated tomake (*) chloroform. This compound is stored in ice in clathrates. After carbon dioxide, this compound is thesecond most common greenhouse gas emitted by humans. It is the most reduced form of carbon. One mole of thiscompound combusts with oxygen to form one mole of carbon dioxide and two moles of water. For 10 points,name this tetrahedral alkane found in natural gas, with formula CH4.

methane [or CH4 until it is read]

The logarithm of viscosity is linearly related to the logarithm of this quantity in the Mark-Houwink-Sakurada equation. Osmometry experiments measure the number-average form of this quantity. The polydispersity index measures the variance of this quantity in a polymer. This quantity is empirically calculated as the cryoscopic constant times mass fraction divided by the change in temperature. The rate of (*) effusion is inversely proportional to the square root of this quantity according to Graham's Law. For an ideal gas, it equals the density times RT over the pressure. For carbon dioxide, it's 44. For 10 points, name this quantity, the sum of the atomic masses in a molecule.

molar mass [or molecular mass; or molecular weight; or formula weight; prompt on mass or weight]

This state property is the only one which explicitly does not follow Gibbs' theorem. In an Ottocycle, there are two isentropic steps and two steps where this quantity remains constant. The slope ofa coexistence curve equals the difference in entropy divided by the difference in this quantity for thetwo phases, according to the Clapeyron equation. Both terms of the van der Waals equation have thisquantity in the (*) denominator. When this state variable is held constant, heat added to the system equalsthe change in internal energy, such as in a bomb calorimeter. This quantity is proportional to temperatureand inversely proportional to pressure for ideal gases. For 10 points, name this quantity which is measuredin liters.

molar volume

8. The Margules activity model expands excess Gibbs free energy as a power series of these quantities. This quantity for the light key, calculated on a solvent-free basis, is plotted on the axes of a McCabe-Thiele diagram. Liquid-liquid extractions are planned using diagrams where three forms of this quantity are plotted on the three sides. The phase diagram of steel plots temperature against this quantity for (*) carbon. Two forms of this quantity symbolized lowercase x and y relate the vapor pressure and total pressure at vapor-liquid equilibrium in Raoult's law. Dalton's law sets a gas' partial pressure equal to this quantity times the total pressure. For 10 points, name this quantity, the percentage a single component occupies in a mixture.

mole fraction [accept mass fraction; accept percentage in place of "fraction"; prompt on concentration; do not accept or prompt on partial answer] <Silverman, Science - Chemistry>

8. An X denotes the non-crossing rule on state correlation diagrams plotting these structures against energy. These structures must maintain their overall symmetry between reactants and products in an allowed peri·cyclic reaction. The stabilization energy for forming these structures is highest when their substituents have similar symmetry and energy to mix the best. These structures are plotted on horizontal lines in the middle of a diagram that uses dashed diagonal lines that indicate the (*) linear combinations that formed them. When these structures are formed in pairs, the higher-energy one is labelled with an asterisk to indicate that it's antibonding. For 10 points, name these structures labelled by Greek letters like sigma and pi, which form when atomic orbitals combine.

molecular orbitals [accept MOs; prompt on orbitals] <Silverman, Science - Chemistry>

In chromophores, electrons in lone pairs are symbolized by this letter, and are forbidden totransition to pi star states. A quantity symbolized by this letter equals molarity times the number ofacidic protons in a strong acid. This letter designates doped semiconductors with more electrons thanholes. The difference between the reciprocal-squares of two values symbolized by this letter gives theenergy of an electronic transition in the (*) Rydberg formula. This letter is often used before the namesof straight-chain alkanes. The principal quantum number is symbolized by this letter. For 10 points, namethis letter which designates number of moles in the ideal gas law, and is the atomic symbol of the gasmaking up most of our atmosphere.

n

Ions of this metal coordinate with the substrate of the first enzyme to be crystallized. An isotope of this metal slightly beats two isotopes of iron for the highest nuclear binding energy. An alloy of it with iron has a very low coefficient of thermal expansion, named Invar. Urease (YUR-ee-ace) contains this metal. It is alloyed with aluminum in a hydrogenation catalyst named for (*) Raney (RAIN-ee). Cadmium and this metal's oxide comprise a popular class of rechargeable batteries. It is purified by complexation with carbon monoxide in the Mond process. The three ferromagnetic elements at room temperature are iron, copper and this element, all right next to one another on the periodic table. For 10 points, identify this element symbolized Ni.

nickel [or Ni until read] <Prieto, Science - Chemistry>

This substance comes in "white fuming" and "red fuming" varieties at 16 molar concentration. It is commonly mixed with water at 68% concentration, at which it forms an azeotrope. Modern methods of producing pure forms of this strong oxidizing agent involve dehydrating the product with sulfuric acid and bubbling the reactant through hydrogen peroxide instead of water. Its large-scale production is done by mixing five equivalents of diatomic oxygen with four equivalents of (*) ammonia in the presence of a platinum/rhodium catalyst in the Ostwald process. Its pKa is approximately negative 1, and mixing it with hydrochloric acid gives aqua regia. For 10 points, name this compound with formula HNO3, a very strong acid.

nitric acid [accept HNO3 or nitrate before mention; prompt after]

This compound and water are produced in a process found in Brocadia and other bacteria with distinctive ladderane lipids. This gas is produced in a specialized organelle with a riboplasm and paryphoplasm, which is known as the anammoxosome (anna-MOX-oh-some). Oxygen often interferes with the reduction of this element, which can be alleviated by leghemoglobin (leg-hemoglobin). An enzyme that reduces this compound relies on an (*) iron molybdenum cofactor found in the legume-associating Rhizobium bacteria. Diazotrophs can aid "fixation" of this compound and convert it to ammonia. This element, phosphorus, and potassium are the major ingredients of fertilizers. For 10 points, name this gas, central to a biogeochemical cycle, which makes up the majority of the atmosphere.

nitrogen [or dinitrogen gas; accept N2] <Wang, Science - Biology>

The ab initio IGLO method calculates the outcome of this technique, which is used to generatedelta-sub-sigma values for carbocations. At very low temperatures, this procedure is used to detectthe ring flips of cyclohexane. Ring currents shift the results of this technique downfield. TMS is astandard in this technique, and deuterated (*) chloroform is often used as its solvent. The readout of thisprocedure has chemical shift on the x-axis. In this technique, a proton adjacent to a methyl group producesa quartet due to spin splitting. Two common forms of it measure the absorption of radio waves bycarbon-13 and by protons. For 10 points, name this form of spectroscopy that uses a magnetic field todeduce chemical structures, which is used in MRIs.

nuclear magnetic resonance [or NMR; or proton NMR; or other forms of NMR]

Syntheses of molecules with this property often employ auxiliaries via asymmetric induction. The fact that Mosher's acid has this property allows it to be used as a derivatizing agent to change the NMR shift of other molecules with this property. Meso compounds notably do not have this property due to a plane of symmetry, and it was first studied in crystals of tartaric acid by Louis Pasteur. Molecules with this property are labeled as R or S using the (*) Cahn-Ingold-Prelog rules. Molecules with this property rotate plane polarized light, meaning they are optically active. For 10 points, name this property of some molecules which makes them distinct from their mirror images, which can be roughly defined as handedness.

chirality [accept word forms; accept things like they have a chiral center; accept word forms of optical activity until mention, prompt after; prompt on "stereochemistry" or word forms; prompt on "stereoisomers" or word forms; prompt on "enantiomers", "diasteromers", "epimers", "anomers" or word forms]

This species is disproportionated by reacting with sodium hydroxide in the Hooker process. In theclassic example of the reactivity-selectivity principle, this molecule abstracts any hydrogen from ahydrocarbon. Addition of this species to carbon monoxide makes phosgene. This oxidizing agent forms when acid reacts with bleach. Homolytic bond cleavage of this molecule is the first step in the Born-Haber cycle for (*) table salt. It forms at the anode when brine is electrolyzed. Before Zyklon B and mustard gas, Fritz Haber weaponized this molecule for the Germans in World War I. For 10 points, name this molecule which is added to water to sterilize it, a diatomic yellow poisonous gas composed of the second halogen.

chlorine gas [or Cl2 ]

The results of this technique are interpreted by tree diagrams, where each branch is separated by a distance labelled J. This technique applies a Fourier transform to the free induction decay profile. The n-plus-1 rule predicts signals in this technique occur in ratios like 1-to-2-to-1 or 1-to-3-to-3-to-1. This technique's apparatus is a superconductor suspended in a dewar of liquid helium, suspended in a dewar of liquid nitrogen. Since heavy water is undetectable in this technique, it or deuterated (*) chloroform is used as the solvent. This technique works for any atom with an odd number of protons plus neutrons; usually, however, it uses carbon-13 or hydrogen. For 10 points, name this technique that applies a strong magnetic field to a sample to induce spin flips, which is used in MRIs.

nuclear magnetic resonance [or NMR] <Silverman>

Multi-angle scattering is used in conjunction with a dextran-based polymer in the size-exclusion type of this technique. Dividing the migration distance of the analyte by the migration distance of the solvent gives the retention factor in this technique. Iodine vapor is used as a developer in a simple version of this technique, and mass spectrometry relies on initially using the gas or (*) high-performance liquid versions of this technique. All forms of this technique rely on the differing partition coefficient of an analyte for a stationary phase versus a mobile phase. Silica plates are used in the thin-layer version of this technique, which is used to determine the components of dyes. For 10 points, name this chemical technique used to separate mixtures.

chromatography [accept more specific answers, eg thin-layer chromatography, HPLC, liquid chromatography, gas chromatography, etc]

An equation that governs this technique is HETP equals A plus B over u plus u times c; that equation is the van Deemter equation. A spectrophotometer may be used to analyze results in this technique where the eluent carries the eluite. (*) Alumina or silica gel are used as substrates in this technique that produces R-sub-f values. Types of this technique include column, thin-layer, and paper, and it can be used to separate ink and water. For 10 points, name this laboratory technique which uses mobile and stationary phases and separates mixtures by their speed travelling through a medium.

chromatography [accept specific types] <BC>

The "tailing" factor is applied in this technique when its output, a series of Gaussian peaks, is asymmetrical. An equation governing this process is usually written "A plus B over u plus C times u equals HETP." Purification of monoclonal antibodies with this technique relies on cation exchange and protein A resins. Most DNA extractions end with a (*) wash step done after this procedure, called an elution. The resolution of this process is given by a ratio of residence times. The canonical form of this technique breaks plant pigments into their individual components. For 10 points, name this separations technique in which a mobile phase moves past a stationary phase, which comes in thin-layer and paper forms.

chromatography [or high-performance liquid chromatography; or paper chromatography; or affinity chromatography; or other forms of chromatography] <Silverman>

The oxo process uses a catalyst containing this metal bonded to four carbonyl groups, which isuseful for hydroformylations. To prove parity violation, the Wu experiment used atoms of thiselement. The first Werner coordination complex contained this metal bonded to four ammines. Thiselement's chloride forms a hexahydrate that is purple in color, but is blue when desiccated. Thiselement is found in a (*) corrin ring in a biological compound required for the synthesis of odd-chain fattyacids. That vitamin, which requires intrinsic factor for its absorption, is B12. This element, iron, and nickelare ferromagnetic. For 10 points, name this transition metal which forms a namesake blue glass, and whichlies right after iron on the Periodic Table.

cobalt [or Co]

The negative sixth power of a counterion's charge determines the CCC of these systems,according to the Schulze-Hardy rule. A critical parameter for these systems is proportional to thesquare root of permittivity times temperature over density times ionic strength. A model for thesethermodynamically unstable, kinetically stable, systems proposes they have electrostatic repulsionsfrom a shell of mobile ions which form a (*) double layer. Peptization stabilizes these systems, though, athigh separations, they also have local minima in energy due to flocculation. Blue light is strongly reflectedby them in the Tyndall effect. For 10 points, name these systems in which particles are dispersed in anothermedium, which include sols, gels, and emulsions.

colloids [prompt on dispersions; prompt on emulsions; prompt on gels; prompt on sols or aerosols; prompt on foams]

The "open-cup" and "closed-cup" methods are used to measure the temperature at which this process occurs. This process occurs industrially in an RTO line. Inerting prevents this process by lowering the concentration below the LEL. This process is done to a sample during carbon-nitrogen-hydrogen elemental analysis. The Zeldovich mechanism shows how this process forms (*) NOx (NOCKS) species. This process is isochoric (eye-so-CORE-ick) in an Otto cycle and isobaric in a Diesel cycle. A reaction's enthalpy is estimated by subtracting the enthalpy of this process for the products from that of the reactants. Catalytic converters mitigate the "incomplete" form of this process, which makes carbon monoxide. For 10 points, name this reaction in which a hydrocarbon is oxidized to water and CO2 in the presence of fire.

combustion [or word forms; or burning; or thermal oxidation; or flashing; or flash point; or explosion; or word forms; prompt on heating; prompt on oxidation or word forms] <Silverman>

The metallochaperones Atx1 (A-T-X-one) and Ccc2 (C-C-C-two) regulate intracellular levels of this metal. For eukaryotes, zinc and this metal are contained in the enzyme superoxide dismutase (dis-MYOO-tase). An alloy of this element, indium, gallium, and selenium comprises a thin film layer in a type of second-generation solar cell. After chromium, this is the lightest element that violates the (*) aufbau (OWFF-bough) principle, due to the transfer of a 4s (four-S) electron to complete the 3d shell. Aldoses turn brick red in a solution containing this metal's sulfate, Benedict's reagent, although it produces a blue-green color in flame tests. For 10 points, identify this element found above silver and gold on the periodic table, whose symbol is Cu.

copper [or Cu until read] <Prieto, Science - Chemistry>

Peptide bonds are reduced by this element in the Lowry assay for protein concentration. Complex IV of the ETC relies on iron and this element exchanging electrons. This element's tetraammine complex is colored indigo, making it a great detector for ammonia. The original high-temperature superconductors were oxides of this element. It only forms +1 and +2 oxidation states. This element and (*) zinc made up a Daniell cell, the prototypical galvanic cell. The standard for electrical conductivity is given relative to this element. This element reacts with carbonates to form verdigris. It alloys with both zinc and tin to make brass and bronze respectively. For 10 points, name this metal found right above silver and gold on the Periodic Table.

copper [or Cu]

In conformal field theories, it is at this point the correlation length becomes infinite. At this point both the first and second derivatives of pressure with respect to volume are zero. At this point for a binary mixture, density fluctuations of increasing wavelength cause the mixture to become cloudy. A popular solvent used in decaffeination reactions is carbon dioxide pushed past this point, and at this point that the enthalpy of vaporization becomes (*) zero. This point, which occurs at 647 kelvin in water, is the endpoint of the liquid-gas boundary. For 10 points, name this point on a phase diagram at which a substance is neither a liquid or a gas, but a homogenous mixture of both.

critical point [or supercritical]

The rate of this process varies with the exponential of the interfacial energy cubed times molecularvolume squared, and the critical radius at which it occurs equals twice the surface energy over theGibbs volume energy. Louis Pasteur used this process to separate the enantiomers of sodiumammonium tartrate. A purification technique making use of this process takes a slurry and dissolvesimpurities in a hot common solvent. This process requires a "seed" upon which (*) nucleation canoccur; otherwise, during fusion, supercooling occurs rather than this process. Supersaturated solutionsspontaneously undergo this process. For 10 points, name this process similar to precipitation which formsordered, solid products from a solution.

crystallization [or recrystallization; or crystal formation or same-knowledge equivalents; prompt on nucleation before it is read; prompt on precipitation; prompt on freezing]

Particles in these materials have quasimomenta proportional to their wavevectors, which exist inthe reciprocal space used to describe their structure. The Hall-Petch relationship describes how tostrengthen these materials by altering their grain boundaries. Symmetries of these materials aredescribed by space groups, while Burgers vectors describe the magnitude and direction ofdislocations in them. Miller indices denote planes in the Bravais (*) lattices that describe translationalsymmetries in these substances. Their fundamental unit is called the unit cell, and may be body- orface-centered cubic. For 10 points, name these solids which are made up of ordered arrangements of atoms.

crystals [or crystal lattices; prompt on periodic media; prompt on lattices until it is read]

A chemical formed from potassium, iron, and this ion is often used to color bronze sculptures. The Elsner equation maintains an 8 to 1 ratio between this ion and oxygen and this ion is often used in gold mining because it is a strong base. This ion is found naturally in plants such as manioc and (*) almonds. This ion is poisonous for humans, as it inhibits cytochrome c oxidase, an important part of the electron transport chain. Zyklon-B’s toxicity was due to, for 10 points, what ion which produces a common poison when bound to hydrogen, with formula CN-?

cyanide [accept CN- before read] <AJ>

Ladderane molecules are comprised of repeats of this kind of molecule. Large examples of these compounds have steric interactions between flagpole hydrogens, while small examples of them exhibit so-called "banana bonds" due to angle strain. Connected molecules of this kind can be described as "fused." A molecule must be planar, conjugated and have this property to be considered (*) aromatic. Haworth projections display sugars as these systems, whose substituents are easily viewed as either axial or equatorial. A certain alkane with this property has chair and boat conformations. For 10 points, identify these molecules which typically have the prefix "cyclo," such as cyclohexane.

cyclic compounds [or rings; or ring systems; or heterocycles; or macrocycles; or cycloalkanes; or cyclohexanes; or cyclobutanes; or cyclopropanes; prompt on aromatic] <Prieto>

High-spin complexes form when the pairing energy is greater than the energy difference betweentwo of these objects. The interaction of these objects with a carbonyl LUMO weakens the bondstrength of the carbonyl in pi backbonding. These objects split into two classes, t-sub-2g and e-sub-g,when approached by a donor. Electronic transitions between these objects results in brightly colored(*) complexes according to crystal field theory. One of these objects has the shape of a dumbbell separatedby a torus and lies on the z-axis. These objects have two nodal planes and correspond to an angularmomentum quantum number of 2. A 4s electron preferentially fills one of these orbitals in copper. For 10points, name these orbitals first filled by transition metals.

d orbitals

In a bipolar junction transistor, the length scale of this process limits the width of the base, and itoccurs in both directions across the junction. A coefficient important to describing this process takesinto account tortuosity, porosity, and hindrance. A law describing this process states that its timeincreases with the square of the distance travelled, and another law describing it states that its flux isproportional to the negative gradient of the (*) chemical potential. Those two laws are named for Fick.When this process occurs across a semipermeable membrane with water, it is called osmosis. For 10 points,identify this process by which particles move from areas of high concentration to low concentration.

diffusion [generously anti-prompt on "osmosis" until mention]

It's not a chemical reaction, but the temperature dependence of this process in a solid can be modeled using the Eyring equation and transition state theory. Two particles with opposite charges can undergo this process in an "ambipolar" fashion. Either ion implantation or this process are the main methods used in industry to dope semiconductors. The heat equation is sometimes named for this process, since (*) convection and this process are governed by the same mathematical laws. The flux of this phenomenon is equal to minus a namesake coefficient times the gradient of concentration according to Fick's Law. For 10 points, osmosis is an example of what form of passive mass transport, in which atoms move from high to low concentration?

diffusion [prompt on mass transport or passive transport] <Busse>

The capillary and diaphragm techniques measure a constant quantifying this process, and for lowReynolds number, that constant equals Boltzmann's constant times temperature over six pi timesviscosity times particle radius. This phenomenon is used to introduce interstitial defects into crystals,such as carbon substitution for steel. This process controls the (*) rate of catalytic reactions with veryhigh turnover numbers. A gradient of chemical potential is the thermodynamic driving force for thisprocess. This process occurs through random walk in Brownian motion, and when it occurs through asemipermeable membrane, it's called osmosis. For 10 points, name this movement of molecules from highconcentration to low concentration.

diffusion [prompt on osmosis before it is read]

12. A typical radical polymerization is terminated by a radical combination or a reaction of this name. Enzyme mediated reactions of this type eliminate superoxide radicals from biological systems. One of these reactions drives the high-pressure CO method for producing nanotubes; that reaction of this type is named for Boudouard. Non enolizable aldehydes may under one of these reactions in the presence of base that produces an (*) alcohol and a carboxylic acid. Peroxidases such as catalase promote this kind of reaction, producing water and oxygen gas from hydrogen peroxide. These reactions are the opposite of comproportionations. For 10 points, name these reactions in which two identical species undergo a redox reaction with each other.

disproportionation reaction [accept dismutation reaction; prompt on redox reaction; prompt on reduction-oxidation reaction; do not prompt on "reduction" or "oxidation"] <Wang, Science - Chemistry>

An apparatus that allows this technique to be applied to air-sensitive substances uses three Teflon taps and is called the Perkin Triangle. One variant of this technique uses a Vigreaux column, which separates the mixture into several trays with different temperatures. A cold finger or a jacket condenser can be used in one arm of this technique's apparatus, and this technique commonly employs reflux to increase yield. (*) Entrainers allow the breaking of azeotropes in this procedure. This technique separates a mixture of compounds that differ in boiling point and takes that evaporate and condenses it in a separate container. For 10 points, name this chemical separation technique, which is often applied to fermented solutions to create alcoholic beverages.

distillation

Moderator Note: Very clearly pronounce the “a†in “thial†Raney nickel can remove these structures in the production of cyclohexane. In a bridged ring system with under 8 carbons, these structures cannot appear at the bridgehead, by Bredt’s rule. Thial compounds contain one of these structures between sulfur and carbon atoms and (*) geometric isomerism is due to these structures. Hydrocarbons with exactly one of these structures have a carbon-hydrogen ratio of 1 to 2, and these bonds contain one sigma and one pi bond. For 10 points, name this bond where two electron pairs are shared between two atoms.

double bonds [prompt on bonds before “1 to 2â€] <BC>

Normal modes that transform as a quadratic function of position will change this quantity. It's not volume, but this quantity squared, over radius to the sixth, times the harmonic mean of ionization energy, equals the long-range interaction energy in an ideal gas. This quantity must change for a vibration to be observed in Raman spectroscopy. In Pearson's theory, soft acids and bases have high values for this quantity, which is higher for iodide than for fluoride. (*) London dispersion forces scale with this property, which is roughly proportional to molecular surface area. This quantity is the ratio of induced dipole moment to the external electric field. For 10 points, name this quantity symbolized alpha, which measures how easy it is to distort an electron cloud.

electric polarizability [or word forms; or alpha until it is read; prompt on molecular size or volume or similar answers] <Silverman>

One version of this technique is aided by collecting an EELS spectrum. Uranyl acetate is used innegative-staining protocols for this procedure, and samples are preferentially prepared in vitreousice for one version of this technique. A cryogenic version of this technique can be used insingle-particle reconstruction. One type of this technique requires using a microtome to take sections,while another requires (*) coating the surface of the sample with a metal. Aberration limits the resolutionof this technique to around 2 picometers, which is much better than techniques using light. For 10 points,name this technique which comes in scanning and transmission varieties, which uses negatively-chargedparticles to image sub-cellular structures.

electron microscopy [or EM; prompt on "microscopy"; accept more specific answers like scanning electron microscopy or transmission electron microscopy before mentioned]

The Felkin-Anh model places the group with the highest value for this quantity orthogonal to thecarbonyl. Groups with a high value of this quantity always serve as deactivators of EAS reactions.One form of this quantity is equal to the effective nuclear charge divided by the square of thecovalent radius, while another form expresses it as the arithmetic mean of the (*) ionization energyand the electron affinity. Those are the Allred-Rochow and Mulliken scales. The difference in this quantitybetween two atoms determines whether their bond is ionic or covalent. Fluorine has the highest value forthis quantity with a 4.0 on the Pauling scale. For 10 points, name this quantity which describes how well anatom attracts electrons in a bond to itself.

electronegativity

4. Ortho/para groups with high total values of this quantity activate benzene for nucleophilic aromatic substitution. IUPAC (I-U-pack) nomenclature requires empirical formulas to be written so this quantity increases from left to right. At positions where this quantity is high, the formal charge is more positive than the oxidation state. Protons adjacent to groups with high values of this quantity, such as nitro, are shifted downfield in NMR and become more acidic due to the (*) inductive effect, since their conjugate bases are stabilized. Hydrogen is assigned 2.2 on a scale for this quantity that ranges between 0.8 and 4.0. Differences in this quantity establish bond polarity. For 10 points, name this quantity that is highest for fluorine on the periodic table.

electronegativity [or electron-withdrawing ability; or EWG; accept specific electronegativity scales such as Pauling electronegativity or Mulliken electronegativity] <Silverman, Science - Chemistry>

The AMBER software package maps this scalar quantity to molecular structure. The standard unit for this quantity in quantum chemistry is the hartree. The Bornâ€"Oppenheimer approximation allows two forms of this quantity to add independently. Variational methods minimize this quantity. Franckâ€"Condon and Jablonski diagrams implicitly plot this quantity along the (*) vertical axis. Transition states are saddle points on a plot of this quantity against the reaction coordinate. This quantity is the eigenvalue of the Hamiltonian in the Schrödinger equation. Degenerate orbitals have the same value for this quantity, which determines the order in which electrons fill orbitals according to the aufbau (OWFF-bow) principle. For 10 points, name this quantity that, like work, is measured in joules.

energy [or potential energy; or orbital energy; or electron energy; or kinetic energy; or free energy; or Gibbs free energy] <Silverman>

The temperature dependence of the change in this quantity is given by Kirchoff's law in terms ofthe change in specific heat. The change in this quantity when dissolving a substance at infinitedilution is zero for an ideal solution. Its differential equals TdS + Vdp, and its partial derivative withrespect to temperature is the heat capacity at constant pressure. The change in this quantity equalsthe (*) heat transferred in a reaction at constant pressure. The Born-Haber cycle calculates this quantity forionic lattices using the fact that this quantity is a state function and hence path-independent, as stated byHess's law. It is equal to internal energy plus pressure times volume. For 10 points, name thisthermodynamic quantity symbolized H.

enthalpy

This quantity for a lattice can be deduced from the Born-Haber cycle and can be derived in the Born-Landé equation. This quantity, which does not change in the Joule-Thomson Process, can be calculated using a calorimeter based on the equation q equals C-sub-v times the quantity T-sub-f minus T-sub-i. (*) Hess’s Law states that this quantity in a reaction is equal to the difference of the sums of this value for the products and reactants. Equal to Gibbs free energy plus temperature times the change in entropy, for 10 points, name this quantity symbolized H, the total heat constant.

enthalpy [accept lattice enthalpy or lattice energy before “Joule-Thomsonâ€; prompt on H] <AJ>

These species are classified under the E.C. system with four distinct numbers. The burst phase model explains the behavior of these species, which can be tracked with para-nitrophenolate formation. The Briggs-Haldane derivation assumes a low concentration of these species. A mass balance around this species, coupled with the (*) quasi-steady state assumption, is used to define their maximum velocity. An increase in their concentration decreases the y-intercept on a Lineweaver-Burke plot, and their reaction rate is always first-order according to the Michaelis-Menten equation. Induced fit and lock-and-key models describe them. For 10 points, name these proteins whose names usually end in "ase," which catalyze biological reactions of substrates.

enzymes [prompt on catalysts prompt on proteins] <Silverman>

8. The Eyring equation sets the bimolecular rate constant to be a form of this quantity times the frequency of successful vibrations. For ligand-metal complexation, this quantity is symbolized beta. This quantity typically ranges between a nanomolar and a micromolar and is subscripted with a D to quantify binding affinities in biochemistry. Though activities are needed to make this quantity dimensionless, integer powers of RT are used to convert its units between (*) concentration and pressure. This quantity decreases with temperature for exothermic reactions. It equals the product of species' molarities raised to their stoichiometric coefficients by the law of mass action. For 10 points, name this ratio between a reaction's forward and reverse rate constants.

equilibrium constant [accept Keq or stability constant or dissociation constant or KD; accept formation constant or binding constant; prompt on K alone] <Silverman, Science - Chemistry>

For a complex, this value increases down the Irving-Williams series. The negative of this value isthe slope of a line in a Scatchard plot. One form of this quantity can be converted into another bymultiplying by RT raised to the difference in the number of moles of gas. The change in this quantityfor a given change in temperature is related to the enthalpy of the reaction by van't Hoff's equation.The change in Gibbs free energy for a (*) reaction equals negative RT times the natural log of thisquantity. The law of mass action equates this value to the concentrations of the products divided by theconcentrations of the reactants. For 10 points, name this constant representing a chemical system where theforward and reverse reactions have the same rate.

equilibrium constant [or K; accept stability constant, association constant, dissociation constant, or binding constant]

This compound and water constitute the canonical example of negative volume change from mixing. Benzene and cyclohexane are added to entrain aqueous solutions of this compound. A phase diagram of this compound with water has a relative minimum at 78.2 degrees Celsius, indicating a positive deviation from Raoult's Law. Hydration of the simplest (*) alkene makes this compound. This compound is fully oxidized by chromate to give acetic acid and water in a basic analytical test. Although it is fully miscible with water, at 96 mole percent, this compound forms a notorious azeotrope during distillation. In the body, it is converted to acetaldehyde by ADH, or alcohol dehydrogenase. For 10 points, name this two-carbon alcohol.

ethanol [or ethyl alcohol; or C2H5OH; or C2H6O; prompt on alcohol] <Silverman>

Mutations in an enzyme which oxidizes this substrate are the basis of the McDonald-Kreitman test.A Cys-46, Cys-174, His-67, and a critical zinc ion surround it in the active site of a protein whichoxidizes this compound. This compound precipitates DNA from aqueous solution. Biosynthesis of thiscompound and carbon dioxide increase in the absence of oxygen according to the Pasteur effect. Like(*) lactate, synthesis of this compound regenerates NAD in the cytosol. A 70% solution of this compoundis used in molecular biology labs to kill microbes. The oxidation of this compound into acetaldehyde isoften faster in Han Chinese and Korean populations, causing the "Asian glow" phenomenon. For 10 points,name this compound, which yeast form in fermentation.

ethanol [or ethyl alcohol]

One of these compounds is produced as a byproduct when reacting aromatic rings with hydrogen chloride and formaldehyde in the Blanc chloromethylation. An allyl vinyl type of these compounds participates in a [3,3] sigmatropic rearrangement in the Claisen rearrangement. A silyl enol type of these compounds is attacked by a chloride in the Mukaiyama aldol reaction. A common polar aprotic solvent, tetrahydrofuran, is a cyclic example of these types of compounds. A synthesis of these compounds involves an (*) alkoxide ion and an alkyl halide in a SN2 reaction, and the best known of these compounds, its diethyl type, was commonly used as an anesthetic. For 10 points, name this class of organic compounds, which are characterized by two alkyl or aryl groups singly bonded to the same oxygen.

ether <Hao>

Union Carbide's UNIPOL process polymerizes this compound, which reacts with itself over a chromium oxide catalyst in a process developed by the Phillips Company. PVC is made by reacting this compound with chlorine, then polymerizing the product. This compound is the most common product of gasoline steam cracking. Ziegler and Natta first used titanium chloride to polymerize this compound, which forms an atactic polymer classified as either (*) "low-density" or "high-density" based on its molecular weight. Adding two equivalents of water to this compound makes the glycol in commercial antifreeze. The polyolefin named for this compound is a linear chain of saturated sp3 carbons and is used in plastic bottles and bags. For 10 points, name this two-carbon alkene.

ethylene [or ethene; or polyethylene] <Silverman>

15. The greatest possible value for this quantity for a molecule is the x-value of the right end of the K-edge in a XANES (zayns) spectrum. The London dispersion force between two atoms depends on their harmonic mean for this quantity. A metal's contribution to a Born-Haber cycle equals its heat of sublimation plus this quantity. This quantity, which is equivalent to the energy of the HOMO, can be calculated from the Rydberg equation by setting one of the Ns to infinity. It increases from (*) left to right and from bottom to top of the periodic table and is highest for helium, since He+ (“H-E-plusâ€) is very unstable. The magnitude of this quantity equals a monovalent cation’s electron binding energy. For 10 points, name this quantity, the energy required to remove an electron from an atom.

first ionization energy [or ionization potential; or ionization enthalpy; or electron binding energy before mentioned] <Silverman, Science - Chemistry>

19. The biological component of an activated sludge is created by inducing this process to bacteria. EDTA suppresses this undesirable process induced by zymolectins in batch yeast fermentations. When this process is used as a separation technique, it is followed by a sedimentation step. Small, highly charged cations and anions induce this process by reducing the impact of Coulombic repulsions versus van der Waals attractions. Species like alumina that induce this process during wastewater treatment are called clarifying agents. This process, the reverse of peptization, is thermodynamically favorable but must be preceded by (*) coagulation to form smaller particles. For 10 points, name this process of destabilizing a colloid by forming clumps.

flocculation [or word forms; or coagulation or word forms until it is read; or coalescence or word forms] <Silverman, Science - Chemistry>

This process "activates" cell sorting in the most common method of flow cytometry. This process corresponds to the decay from S1 to S0 without internal conversion on a Jablonski diagram. This phenomenon is "recovered" after photobleaching in a technique used to study the cell membrane. The Stern-Volmer equation gives the decrease in quantum yield of this process in the presence of (*) quenchers. A common reporter protein which undergoes this process has a serine-tyrosine-glycine motif in a beta barrel. An arrow drawn from the excited to ground state represents this phenomenon, in which electrons absorb energy, and then emit at a lower wavelength, generating light. For 10 points, name this type of luminescence shown by GFP.

fluorescence [or word forms; prompt on luminescence]

The Tanabe-Sugano diagram for this many d electrons is the first with a vertical linediscontinuity. The "oxo wall" states this is the maximum number of valence d-electrons in oxocomplexes. A linear triatomic molecule has this many vibrational degrees of freedom. Thecycloalkane with this many carbon atoms has two butterfly conformers. Four of the five 3d orbitals,but not the 3d sub z-squared orbital, have this many (*) lobes. This is the lowest principal quantumnumber for f-orbitals. The first binary compound of a noble gas consists of xenon bonded to this manyfluorine atoms. This is the number of ligands in molecules with the see-saw and square planar geometries.For 10 points, give this number, which also gives the atomic number of beryllium.

four

One method of detecting the distance between a pair of these species is the PELDOR experiment.Introducing species like PNO, DMPO and TEMPO to short-lived versions of these species createsnitroxide-based persistent ones, which can then be imaged by Electron Paramagnetic ResonanceSpectroscopy. Halogenation reactions with these species as intermediates tend to lackstereospecificity. These species are created by homolysis when a halogenÂâ€"halogen or halogenÂâ€"carbonbond is cleaved by (*) UV light, which explains why CFCs are damaging. Mitochondria generate thesuperoxide one, which damages DNA. They are reactive because they violate the octet rule, often havingonly 7 valence electrons. For 10 points, name these compounds with an unpaired electron.

free radical [prompt on "spins" before "superoxide"; prompt on "electrons" before mention]

One technique used to image these compounds displays field strength on the x-axis and draws both absorbance and first-derivative curves; that technique commonly uses DMPO or PBN to increase the lifetime of its samples. Sawamoto, Wang, and Matyjaszewski independently discovered a living polymerization technique which uses these compounds, ATRP. These compounds can be analyzed by ESR spectroscopy, and the first of these compounds to be discovered (*), triphenylmethyl, was synthesized by Moses Gomberg. In reactions involving these compounds, fishhook arrows are used. The superoxide one of these compounds is generated in the mitochondria, and they’re neutralized in the body by Vitamins A, C, and E, which are antioxidants. For 10 points, name these very reactive molecules with unpaired electrons.

free radicals <Hao>

The "at" symbol is exclusively used in the chemical formula of these compounds. In nanotweezers, these compounds reversibly bend inward when a voltage is applied across them. They are "doped" with potassium to make superconductors above 18 Kelvin. These molecules have mass of either 720 or 840 amus. They have two different bond lengths: those from 6-6 and 6-5 bonds. These materials dissolve in nonpolar solvents to turn bright (*) purple. These molecules can be synthesized by firing a laser at soot. When rolled into cylinders, they form single or double walls. They can hold entire metal atoms inside an icosahedral body. For 10 points, name these allotropes of carbon which forms soccer-ball shaped "buckyballs."

fullerenes [or buckminsterfullerenes; prompt on buckyballs; prompt on carbon nanotubes]

A trick when creating the matrix for this technique is to use a pipet tip to push bubbles away. Combining this technique with chloroquine is used to tell apart positive and negative supercoiling. Sanger sequencing involves a capillary version of this technique to read the fluorescent markers. This technique is performed before transferring to nitrocellulose paper in Southern Blotting. It is typically performed in tris-acetate buffer, and the (*) intercalating agent ethidium bromide is used to image the results under a UV light. A "ladder" is used as a marker in this technique, which separates fragments based on size. For 10 points, name this technique, in which a current applied to a DNA sample forces it to migrate through an agarose matrix.

gel electrophoresis

In geomelting, radioactive waste is turned into this type of material. Lyophilization of pharmaceuticals occurs at a temperature named for this material. At that temperature, polymers supercooled beyond the "rubber" state transition into a state named for this material. Sensitive pH electrodes are made out of this material. Primary network formers of this substance, like phosphorous oxide, have a decreased melting point because of fluxes, like (*) potash. Hydrofluoric acid reacts with this material to give silicon fluorides. Boric oxide is mixed into this material to prevent thermal expansion. It consists of amorphous silicon oxide. For 10 points, name this material used to make Pyrex beakers and flasks.

glasses [or spin glasses; or glass transition temperature; or glass electrodes]

In the Elsner reaction, this element forms a coordination complex with cyanides. Relativisticcontraction of this metal's outermost s orbital allows it to dimerize, leading to the strongest form ofmetallophilicity. Among metals, this element has the highest electronegativity and electron affinity,and it has the uncharacteristic oxidation states of +1 and +3. A mixture of nitric and (*) hydrochloricacid dissolves both platinum and this element. A ring of zinc sulfide surrounded a sheet of this elementwhich deflected alpha particles, in the experiment where Rutherford proved the existence of the nucleus.For 10 points, name this noble metal located below silver on the Periodic Table, which has symbol Au.

gold [or Au before it is read]

The first self-assembling monolayers were formed by alkane-thiols bonding to this metal. Colloidal particles of this element are used to stain in electron microscopy. A cross-section proportional to the fourth power of the cosecant was first proposed for elastic scattering off this element. This metal has +1 and +3 oxidation states. This metal does not dissolve in nitric acid, but does (*) dissolve in a 1:3 mixture of nitric and hydrochloric acids. This element was described as a piece of tissue paper, deflecting a cannonball, into a ring of zinc sulfide, during the experiment which discovered the nucleus. It is the most malleable and ductile metal. For 10 points, name this element with symbol Au.

gold [or Au until it is read]

10. Arranging this substance in a Moiré pattern was an early investigation in the field of twistronics. This substance can appear in an AB arrangement called the Bernal stack, which commonly forms when using CVD. The name of this compound was first used to describe its appearance in a bronze-colored potassium based intercalation compound. Hybridization with substrate d-orbitals is problematic when producing this compound with (*) epitaxy. Andre Geim found the surprisingly simple method of isolating this substance by exfoliating it with Scotch tape. Like in nanotubes, atoms in this substance are nearly entirely sp2 hybridized and form a hexagonal lattice. For 10 points, name this substance, a single-layered carbon allotrope.

graphene [do not accept or prompt on "graphite"] <Wang, Science - Chemistry>

13. Protein FT-IR measurements are typically carried out in this solvent. The NMR peak corresponding to the acidic proton in an alcohol disappears when this compound is added due to chemical exchange. Despite pioneering a way to purify this liquid through electrolysis rather than distillation, GN Lewis lost out on the Nobel Prize awarded to Harold Urey. Solvent suppression is often necessary because this common NMR solvent is only sold by vendors at 99.9% atomic purity. This compound, a common source of (*) radiolabeled hydrogen, has a mass of 20 daltons and is sometimes used as a coolant and moderator in nuclear reactors. For 10 points, name this compound composed of oxygen bonded to two deuterium atoms.

heavy water [accept deuterium oxide or D2O; do not accept or prompt on "water" or "H2O"; do not accept or prompt on “deuterium†alone] <Silverman, Science - Chemistry>

In the Donnan effect, this quantity seems larger than it actually is because of an electrostatic potential. The main reason cells store glucose as glycogen is to minimize this quantity. A classic method of determining molecular weights measures this quantity for a polymer solution. This quantity times the volumetric flow rate through an RO membrane gives the power required for industrial (*) desalination. It equals the van 't Hoff factor times molarity times RT in the Morse equation, and is zero between isotonic solutions. This quantity, symbolized uppercase pi, is the difference in fluid height between the two halves of a dialysis tube. For 10 points, name this colligative property, which is the number of pascals required to prevent water from diffusing through a membrane.

osmotic pressure [or uppercase pi until it is read; prompt on pressure; prompt on turgor pressure] <Silverman>

6. The binding of this ligand is measured by calculating the red/infrared ratio from two LEDs tuned to 660 and 940 nm. The binding of this species was the first to be described by a Langmuir isotherm where its concentration is exponentiated by n. The binding of this species causes a protein's proximal histidine to shift and changes the protein from a "taut" configuration to a more "relaxed" configuration. Up to (*) four of these species may bind to a certain protein, with each binding subsequently increasing their affinity. This species, which experiences homotopic cooperative effects, binds at an iron atom coordinated by a porphyrin. Carbon monoxide prevents the binding of this gas. For 10 points, name this gas transported by hemoglobin.

oxygen gas [or O2] <Silverman, Science - Biology>

Reacting oleic acid with this compound yields nonanoic acid and azelaic acid. Pyridine can buffer a reaction involving this compound. A spectrophotometer measuring absorption at 305 and 325 nm is used to quantify this substance, whose vertical distribution is determined by the Umkehr method. In one reaction, this compound is bubbled through a solution of an alkene in methanol at negative seventy-eight degrees Celsius. That reaction cleaves unsaturated carbon-carbon bonds. This compound completely decomposes (*) urea into nitrogen, carbon dioxide, and water. Dobson units measure the concentration of this compound, whose smell is often detected after lightning. This pale blue compound exhibits a bent molecular geometry and can be depleted by CFCs. For 10 points, name this allotrope of oxygen with three atoms.

ozone (or O3) <Hao>

The standardized method of measuring this quantity is the Harned cell. One instrument used tomeasure this contains an internal electrode, a reference electrode, and an ion-selective glass tip. Forantimonial compounds, the Hammett function is often used instead of this quantity. Compounds likeTris, MOPS, and HEPES are designed to keep this quantity constant. Popular methods of notingchanges in this quantity involve adding (*) methyl red and bromophenol blue. A sudden jump in thisquantity occurs around the equivalence point of a standard titration, and indicators like phenolphthaleinshow changes in it by changing color. It is found by taking the negative logarithm of the concentration ofhydrogen ions. For 10 points, name this measure of acidity.

pH [prompt on "acidity" or "basicity"; accept pOH until "hydrogen"]

The Kelvin equation gives solubility as a function of this property. Dynamic light scattering is used to measure this quantity, which continuously increases due to Ostwald ripening. The mean free path is proportional to the negative second power of this quantity. This property of a polymer is determined using chromatography where a gel is the stationary phase. The cross section in (*) collision theory is roughly the sum of this quantity for the molecules. The difference between a colloid and a suspension is this property for the particles. The b term in the van der Waals equation accounts for this property, countering the ideal gas law's assumption that this property for gas molecules is zero. For 10 points, name this quantity which is small for particles that pass through a filter.

particle size [or volume; or surface area; or radius; or diameter; or chain length; do not accept or prompt on "mass" or "weight" or "molar mass"]

One method of drawing these diagrams is to produce bundles around invariant points usingSchreinemaker's method. Software packages like THERMOCALC use the CALPHAD method fordrawing these figures. For minerals, this diagram is used to display various polymorphs. Theformula C minus P plus 2 is used to find the degrees of (*) freedom at each point in these diagrams. Forbinary systems, these diagrams can display the eutectic and peritectic points. These plots often showtemperature and pressure on their axes and show coexistence curves as lines. These diagrams also show thetriple and critical points. For 10 points, name these plots that display the state variables at which a systemexists as a solid, liquid, or gas.

phase diagram

Solutions of this ion turn green after adding ammonium heptamolybdate. During Maxam-Gilbert sequencing, this ion is radioactively labeled and incorporated into cells. Two of these ions linked together are given the prefix "pyro." Salts of this anion and chloride compose a common biological buffer that's isotonic to blood. This fully deprotonated molecule has three (*) pKa values at 2.1, 7.2, and 12.7. This ion is called "inorganic" when it's a monomer. The first step of glycolysis attaches this tetrahedral ion to glucose through the enzyme glucokinase. It comprises the polar head groups in the cell membrane, and it links sugars in the backbone of DNA. For 10 points, name this ion with a negative-three charge and four oxygen atoms bonded to a central phosphorus.

phosphate ion [or PO43- until "phosphorus" is read] <Silverman>

Vaska’s complex contains two atoms of this element bonded to iridium, and the nucleophilic addition of this element to a carbonyl carbon begins the Perkow reaction. This element is bonded to three alkyl groups in one of the reactants in the Michaelis-Arbuzov reaction, and this element binds to an azide in the Staudinger reaction. This element is found double-bonded to an oxygen in the nerve agent sarin, and overexposure to this element can cause necrosis of the (*) jaw. The radioactive 32-isotope of this element is used in a Northern blot, and a ylide of this element is reacted to form an alkene in the Wittig reaction. An acid of named for this element has three Ka values, because the polyatomic ion containing this element and oxygen has a -3 charge. This element comes in black, violet, red, and white allotropes. For 10 points, name this element with atomic number 15 and symbol P.

phosphorus <Hao>

19. PDMS is often treated with one of these substances before use to expose surface hydroxyls and enhance adsorption. Dry IC microfabrication relies on these substances to etch silicon wafers. Metals are detected at very low concentrations using a form of mass spectrometry where one of these substances generated through inductive heating (*) ionizes the analyte. These substances are modeled the same as electrolyte solutions since electric fields in them are screened at short distances. In atomic emission spectroscopy, metals are exposed to a flame or to one of these substances made from argon. These highly conductive substances are formed by heating gases until they ionize. For 10 points, name this fourth state of matter.

plasmas [or inductively coupled plasma] <Silverman, Science - Chemistry>

At the theta point, the self-repulsion of these substances matches a random walk model. They aremodeled by an exponentially-decaying correlation function in the Kratky-Porod model. Substanceslike DEHP and DINP can be used to lower the glass transition temperature of these substances. Ifthey can be dissolved and softened to be remolded into their old shape, they are called (*) thermoset.The formation of covalent bonds within these substances leads to an increase in their strength calledcrosslinking. Carothers' equation gives the namesake degree of the formation of these substances, whichcan proceed via a "step-growth" process. A synthetic example of them is Teflon. For 10 points, name theselong molecules made of monomer units.

polymers

18. A model for this class of molecules predicts that their force-extension curves vary as "hyperbolic cotangent of x, minus one over x". These molecules are typically modeled as random walkers that can't cross paths and incur energetic penalties for changing direction. These molecules are characterized by an average persistence length over which they do not bend. Viscometry and size-exclusion chromatography are used to calculate the (*) size of these molecules, which is usually reported as a molecular weight. These molecules become stiffer when crosslinked using processes like vulcanization. They can be catalytically synthesized by heating molecules like styrene and ethylene. For 10 points, name these molecules composed of repeated monomers.

polymers <Silverman, Science - Chemistry>

An explosive reaction between these two species nearly killed a lab assistant of Henry Le Châtelier (on-REE luh shot-lee-AY). The biological reaction between these two species requires a cofactor called FeMoco. Gerhard Ertl won a Nobel in 2007 for uncovering the mechanism for how these two species react on a potassium-loaded iron catalyst. Normally, these two molecules react exothermically in a (*) 1-to-3 molar ratio at very high temperatures and pressures to give two moles of a gas that is condensed and removed from the reaction, driving equilibrium to the right. One of these gases reduces the triple bond in the other to form a trigonal pyramidal compound used in fertilizers. For 10 points, name these two simple elemental gases that react in the Haberâ€"Bosch process to form ammonia.

hydrogen AND nitrogen gas [or H2 AND N2; or protons AND nitrogen gas; or H-plus and nitrogen gas; either order acceptable; prompt on partial answer] <Silverman>

In the active site of chymotrypsin, these phenomena create the oxyanion hole. These phenomena typically occurs over a length scale of 200 picometers, and nylon has several of them between adjacent chains. These phenomena between carbonyl and amide groups are responsible for forming the structure of alpha helices and beta sheets, and they are also present between (*) nucleotide bases on DNA. They are responsible for the high boiling point of water, since one water molecule can form four of these. They are stronger than van der Waals interactions but weaker than ionic or covalent bonds. For 10 points, name these interactions between an electronegative atom and an atom carrying the namesake light element.

hydrogen bonding [or H bonding]

Two of Lipinski's four "rules of five" restrict how much a drug candidate can participate in this effect. The notation "i-plus-four maps to i" describes the orientation of this effect in proteins. PCR annealing temperatures are chosen based on the energy for this interaction between oligonucleotides. Because beta-glycosides but not alpha-glycosides participate in this effect between strands, (*) cellulose is harder to digest than starch. This interaction defines macromolecular secondary structure, since it holds together alpha-helices, beta-sheets, and strands of DNA and RNA. The solvation ability and cohesion of water arise from its participation in this interaction. For 10 points, name this type of strong dipoleâ€"dipole force between oxygen and a namesake light element.

hydrogen bonding [or H-bonding; prompt on partial answer; prompt on base pairing or complementarity] <Silverman>

This molecule is produced along with carbon black in the Kvaener process and along with carbon monoxide in the CPOX partial oxidation process. When exposed to atmospheric moisture, reducing agents like lithium aluminum hydride produce this compound. Its liquid form is stored at its boiling point of 20 Kelvin. This molecule is the lightest component of syngas, a high (*) energy mixture of carbon monoxide and it. Catalysts like palladium are used to add it across a double bond. In the Haber process, three equivalents of this compound are used up per ammonia molecule. O2 and this compound are produced by the electrolysis of water. For 10 points, name this explosive diatomic gas containing two atoms of the lightest element.

hydrogen gas [or H2 or dihydrogen] <Mukherjee>

This ion’s concentration is inversely proportional to hemoglobin’s affinity for oxygen in the Bohr effect. It’s not potassium, but the concentration of this ion is related to hyperkalemia. The movement of these ions can be described by the Q cycle. The drug omeprazole (“oh-mehp-raz-oleâ€) inhibits the production of these ions in (*) parietal (“pah-RY-it-alâ€) cells. Antimycin blocks the transport of these ions through the cytochrome bc1 complex at the start of the electron transport chain, and these ions pass through ATP synthase to make ATP. For 10 points, name these ions donated by Brønsted-Lowry and Arrhenius acids.

hydrogen ions [accept H+ or protons or hydrons] <AJ>

A mutation in the DUOX2 gene can lead to decreased production of this compound in the thyroid. Bombardier beetles mix this compound with hydroquinone to produce their signature defensive spray. This compound is produced in cells by the enzyme (*) superoxide dismutase, and UV light leads to the creation of two hydroxyl radicals in this compound so it is stored in opaque bottles. Catalase catalyzes the decomposition of this compound into oxygen and water and is found in the peroxisome. For 10 points, name this compound with formula H2O2 (“H-two-O-twoâ€) used as an antiseptic.

hydrogen peroxide [accept H2O2 until mention; prompt on peroxide] <BC>

This is the simplest compound exhibiting a "skew chain" dihedral angle of about 120 degrees as acompromise between steric and hyperconjugative effects. mCPBA is synthesized frommeta-chlorobenzoyl chloride and this compound. Potassium iodide catalyzes the disproportionationof this compound, releasing lots of foam. The anthraquinone process makes this compound. Thoughthis compound is not linear, it readily homolyzes into (*) radicals because it has four electrons in pi starorbitals. This very strong oxidizing agent is used to treat wastewater as Fenton's reagent, and in the body, itis broken down by catalase into water and oxygen gas. For 10 points, name this compound with anoxygen-oxygen single bond, and formula H2O2.

hydrogen peroxide [or H2O2 before it is read; prompt on peroxide]

Glucose sensors work by colorimetrically monitoring the formation of this compound when glucose is oxidized. Piranha solution contains it and sulfuric acid. This compound catalyzes the second step of hydroborationâ€"oxidation. A mixture of iron and this compound is used to decontaminate halogenated organic waste in water. This compound forms when long-chain fatty acids are dehydrogenated, but it is immediately (*) disproportionated in cells from a negative-one oxidation state to compounds with zero and negative-two oxidation states by the enzyme catalase. Shining UV light on this compound gives two hydroxyl radicals, so it must be stored in opaque brown bottles, often in a 3-percent aqueous solution, at which point it is used as an antiseptic. For 10 points, name this compound which has formula H2O2.

hydrogen peroxide​ [or H2O2​ until it is read; prompt on peroxide]

7. PDB files only contain positions for these substituents if the protein structures were solved using NMR, not X-ray diffraction. United atom force fields usually coarse-grain over these substituents. Steric clash between two of these substituents at flagpole positions destabilizes boat conformers. This group is assigned the lowest possible priority in CIP nomenclature. Primary carbons are bonded to (*) three of these substituents. The formula "2C plus N plus two" gives the maximum number of them in an organic molecule. This group makes up the side chain of glycine. These atoms are typically implicit in organic structures and are represented by white spheres in molecular modelling kits. For 10 points, name these atoms that weigh one dalton.

hydrogens [or hydrogen atoms; or H; do not accept or prompt on hydride] <Silverman, Science - Chemistry>

11. The extremely high motility of this species is explained by the hop-turn mechanism in which it effectively dimerizes to form a Zundel ion. This species' activity multiplies a ratio of activity coefficients for anilines in the Hammett function. This ion is isoelectronic to ammonia but has a bond angle of 113 degrees. This species' pKa is -1.74, which is the negative logarithm of (*) 55.6. According to the leveling effect, the degree of dissociation of this species is the largest that can be measured in water. The concentration of this cation is equal to the square root of Kw for neutral solutions. Autoionization of water makes hydroxide and this ion. For 10 points, name this polyatomic ion produced by Arrhenius acids with formula H3O+.

hydronium [or H3O+ until it is read; prompt on protons; prompt on hydrons; prompt on oxonium] <Silverman, Science - Chemistry>

10. The formula for the grand potential reduces to this equation if the log Z term equals particle number. This equation is true if, at constant temperature, entropy scales linearly with the log of volume. If this equation is true, then all the departure and residual functions are zero, and the enthalpy depends only on temperature. This equation is generally a decent approximation if the specific volume is greater than (*) 5 liters per mole. This equation is equivalent to setting the compressibility factor to one or when the a and b parameters are zero in the van der Waals equation. A constant found in this equation is approximately 8.314 joules per mole kelvin. For 10 points, name this equation of state used for gases at low pressures and high temperatures that equates PV to nRT.

ideal gas law <Silverman, Science - Chemistry>

In the Goldschmidt classification, species are grouped by whether their preferred host is rock, ores, gas, or this element. This element and a more dense one "rained out" of molten material during the "catastrophe" named for it, a key step in planetary differentiation. Siderophiles are named for their preference for this element, which is said to be (*) "telluric" if it is found on Earth as not part of an ore. This element bonded to sulfur forms galena (guh-LEE-nuh). Ores of this element include a specimen historically called lodestone and the reddish-brown hematite. Fool's gold, or pyrite, is an ore of this metal, which along with nickel is a major element of the Earth's core. For 10 points, name this magnetic chemical element abbreviated Fe.

iron [or Fe until read] <Jose, Science - Earth Science>

An ammonium and sulfate salt of this metal named for Mohr is frequently used in titrations. The first attempted synthesis of fulvalene accidentally created a molecule with an atom of this metal at its center. An enzyme in the Krebs cycle named aconitase has a catalytic center with atoms of this metal and (*) sulfur arranged in a cube. The first synthesized metallocene contained an atom of this metal at its center. This is the lightest element that cannot be used in stellar fusion without a cost in energy, or a supernova will occur. The mineral pyrite contains two sulfur atoms and an atom of this metal, and is commonly referred to as fool's gold. For 10 points, identify this metal found in ferrocene, whose oxide is rust.

iron [or Fe] <Prieto>

When an alkene serves as one of these species, the double bond length tends to increase according to the Dewarâ€"Chattâ€"Duncanson model, which covers a specific case of pi-backbonding. These species may be characterized by their cone angle and bite angle. Phosphines (FOSS-feens) are commonly used as these species, whose presence causes d-orbital (*) splitting predicted by crystal field theory. These species can be characterized as type L, X, or Z depending on if they donate two, one, or zero electrons respectively. When these species bind at multiple sites, their hapticity or denticity is greater than one, and polydentate ones are called chelating (KEE-late-ing) agents. For 10 points, name these species which coordinate to metal centers to form complexes.

ligands (LIG-unds) [prompt on chelates or chelating agents until read] <Wang, Science - Chemistry>

In addition to his work on polymers, Nobel Laureate Pierre-Gilles de Gennes (Pierre-ZHEEL duh ZHEN) wrote a pioneering 1974 textbook about the physics of these materials, which can be affected by an external electric field in the Fréedericksz (FREE-durr-icks) transition. Classes of these materials include thermotropic and lyotropic. They were discovered when Friedrich Reinitzer (RYE-nit-ser) observed two distinct melting points in cholesteryl (ko-LESS-tuh-RILL) benzoate, and possess short-range but not long-range (*) order. A tilt order parameter is necessary when modeling layers present in the smectic phase, while the simplest phase of these materials is the nematic. They are named for having characteristics of both fluids and ordered solids. For 10 points, identify these materials used in electronic displays.

liquid crystals [prompt on partial answer] <Prieto, Science - Chemistry>

4. Kohlrausch names a device for measuring this quantity which can be classified as either "TC" or "TD" at 20 degrees Celsius. Devices from Rainin labelled P-2, P-20, P-200, and P-1000 are used to measure this quantity. This quantity is precisely measured by placing a black paper strip behind the thin glass neck of a namesake (*) flask that has a rounded base. Titration is equivalent to the analysis named for this quantity. Alcohol thermometers work because this quantity increases linearly with temperature in a liquid. This quantity should be measured from the bottom of the meniscus when reading it out on a burette. For 10 points, name this quantity measured using pipettes or graduated cylinders.

liquid volume [prompt on liquid height or liquid level] <Silverman, Science - Chemistry>

Sinapinic acid is most commonly used for this procedure. It often requires helium to be pumped into a collision cell in an intermediate step. This technique is done twice in a row, or in tandem, to sequence proteins. In a common method of prepping this procedure, a laser is fired at a matrix to desorb a sample. The output of this procedure is commonly shown as a bar graph with an M+1 signal right next to the (*) base peak, which is the radical cation formed in this procedure's first step. This technique measures the abundance of each m-over-z ratio in a sample by subjecting fragments to a magnetic field. For 10 points, name this form of spectrometry which distinguishes between isotopes because of the difference in ions' molecular weights.

mass spectrometry

Scattering experiments performed on these molecules are interpreted in Kratky or Guinier plots. The synthesis of these molecules by the ROMP (romp) reaction involves the relief of ring strain. Molecules can be "masked" from the immune system by attaching one of these molecules in the process of PEGylation (peg-ill-AY-shun). The telechelic (tell-uh-KEE-lick) versions of these molecules contain reactive (*) end groups. These molecules can form through "living" reaction mechanisms that propagate through anionic (ANN-ionic), cationic (CAT-ionic), or radical intermediates. The polydispersity (poly-dis-PURR-sit-ee) index characterizes their mass distribution, and DuPont created one of them from chloroprene (CLOR-oh-preen). For 10 points, name these molecules which can be formed by step-growth or chain-growth mechanisms, which include neoprene and nylon.

polymers [accept proteins before "ROMP" is mentioned, prompt afterwards] <Wang, Science - Chemistry>

The Gibbs free energy of mixing for these compounds depends on component volume fractions, not mole fractions, as well as an empirical parameter symbolized chi. Differential scanning calorimetry of them shows a sharp discontinuity below their melting points. The viscosity of solutions of these compounds follows a power law of their (*) molecular weights, whose distribution is described by the polydispersity index. Adding the prefix "co-" to their name indicates different starting materials were used in their synthesis, which often results in branching during the propagation step. Their formation can be described as step-growth or chain-growth, and they are denoted by parentheses around a repeating unit. For 10 points, name these compounds that consist of many monomers.

polymers [or polymer solutions] <Silverman>

This process occurs after combining a basic solution of benzenesulfonyl (benzene-sulf-ON-ill) chloride with a secondary or tertiary amine, but not a primary amine, in the Hinsberg test. Alloys can be strengthened by a process named for this kind of "hardening." It's not reduction, but observing the result of this process is the basis of Fehling's (FELL-ing’s) test. The term (*) "salting out" refers to this process for proteins, which can be triggered with ammonium sulfate for proteins or with ethanol for DNA. Reacting lead cations with almost any anion other than nitrate and acetate results in this process. It is similar to crystallization, but happens much faster and produces smaller crystals. For 10 points, identify this process of forming an insoluble solid from a reaction.

precipitation [or word forms; prompt on crystallization] <Prieto, Science - Chemistry>

Either density or this quantity is used as the variable of integration when calculating residual properties. A truncated virial equation sets the compressibility factor equal to one plus b times this quantity. Cubic equations of state are written as explicit functions of this quantity. Enthalpy equals heat only if this quantity does not change for an open system. The fugacity coefficient is defined as fugacity over this quantity. (*) This quantity equals the liquid-phase concentration times Henry's constant for dilute solutions. Work is the area under a graph plotting this quantity versus volume. This quantity times volume has units of energy, and it multiplies volume in the ideal gas law. For 10 points, name this quantity measured in bars, torr, or atmospheres.

pressure [or partial pressure; do not accept or prompt on "vapor pressure"]

In SN1 reactions, by definition this quantity is linearly proportional to the electrophile concentration, while it is independent in zero order reactions. This quantity’s coefficient is related to temperature by the Arrhenius (“ar-HEE-nee-usâ€) equation, and this quantity is that coefficient, k, times the concentration of each reactant (*) raised to its stoichiometric (“stoy-kee-oh-MEH-tricâ€) coefficient. This quantity times the stoichiometric coefficient is the rate at which a product or reactant changes in concentration. Catalysts raise, for 10 points, what quantity, with unit molarity per second, the speed of a chemical reaction?

reaction rate [accept words in either order; prompt on partial] <DM>

RP Bell modified one equation for calculating this quantity using a tunneling correction factor.This value is calculated using the pre-equilibrium approximation. Classically, plotting the log of thisquantity against one over temperature gives a straight line. The ratio of this quantity when replacingone reactant with deuterium to the original value gives the isotope effect. This quantity is equal to an(*) exponential of negative E sub a over RT all times the pre-exponential factor; that equation relates thisquantity to the activation energy and is named for Arrhenius. The units of this quantity depend on the orderof the reaction. For 10 points, name this value, which is multiplied by concentrations of reactants in orderto find the speed of a reaction.

reaction rate constant

This quantity multiplies residence time in the Damköhler number, and is divided by the diffusivity in the Thiele modulus. The exponential of one-half, times the square root of eight times Boltzmann's constant over pi, appears in a classical derivation for this quantity. The kinetic isotope effect is a ratio of these quantities. This quantity has units of molarity to the one minus n, over seconds, where n is the (*) order. The natural logarithm of two, divided by this quantity, equals the half-life. According to collision theory, this quantity equals a pre-exponential factor times e to the negative activation energy, over RT, by the Arrhenius equation. For 10 points, name this constant which measures how quickly a reaction occurs.

reaction rate constant [prompt on reaction rate; prompt on k]

A large reorganization energy can make reactions of this type that are strongly exergonic enter an inverted region. Cofactor recycling is used in enzymatic catalysis of this type of reaction. These reactions can proceed via an inner-sphere or outer-sphere mechanism. These reactions are balanced for oxygen and hydrogen by adding water, then (*) protons, to each side. A reactivity series is used to determine if these reactions will occur, since they often result in single-displacements. Potassium permanganate is used as an indicator for these reactions. They only occur if the cell potential is positive, when modelled as half-reactions in galvanic cells. For 10 points, name this type of reaction which involves electron transfer.

redox reactions [or reduction-oxidations; or oxidation-reductions; or electron transfer until it is read; prompt on reductions or oxidations specifically]

Metals mixed with silica gels, called M-SGs, are used for this purpose in chemical reactions.Malonic and bromomalonic acid act as these species in the Belousov-Zhabotinsky clock reaction. Inthe Hall-Heroult process, elemental carbon acts as this species, and in organic chemistry, sodiumborohydride and lithium aluminum hydride are a strong type of them. Alkali (*) metals almost alwaysact as these species. This species is the reactant with the smaller standard electrode potential. In thepresence of platinum, hydrogen gas acts as this agent when it reacts with alkenes and alkynes. Thesecompounds will readily give up an electron. For 10 points, name these "agents" which get oxidized in redoxreactions.

reducing agents [or reductant]

This process happens to water vapor in the water-gas shift reaction. Lithium aluminum hydrideand sodium borohydride are common compounds for carrying out these reactions, which mediate itvia hydride transfer. In the Mond process, nickel undergoes one of them to be extracted from its ore.This type of reaction readily happens to permanganate and chromate. Electrodes are often ranked bytheir electric (*) potential for undergoing this process, of which hydrogenation is a subtype. This reactionoften turns positively charged ions into neutral precipitate, and occurs at the cathode of an electrochemicalcell. For 10 points, name this process in which a species gains electrons, often paired with oxidation.

reduction

Iodometry is viable for any compound with a lower value for this quantity than iodide. Reactivity series for single-displacement reactions are ordered by this quantity. This quantity is measured using silver and silver chloride in a one-molar solution of potassium chloride. In SI units, this quantity is 3.06 for fluorine, 1.229 for oxygen, and zero for (*) hydrogen, the last of which is used as a standard for all others. If the change for this quantity is positive, then a redox reaction is spontaneous. At non-standard states, it decreases by RT over nF times the log of the reaction quotient, according to the Nernst equation. For 10 points, name this quantity symbolized by a script E, measured in volts against a reference electrode.

reduction potential [or redox potential; or cell potential; or emf; or electromotive force; or voltage; prompt on energy] <Silverman>

A factor symbolized sigma, representing this property, multiplies the characteristic rotationaltemperature in the denominator of the molecular rotational partition function. The terms gerade andungerade describe this property of molecular orbitals. This property is conserved in orbitals inpericyclic reactions according to the Woodward-Hoffmann rules. Point groups represent thisproperty of compounds. Though meso compounds have a form of this property, no (*) chiralcompounds do. Carbon tetrachloride is nonpolar, even though its bonds are polar, because this property ofthe molecule causes its dipole moments to cancel. For 10 points, name this geometrical property possessedby molecules which look the same when reflected across a point, line, or plane.

reflectional symmetry [or word forms; or specific types of symmetry; prompt on even or odd parity before "chiral" is read]

The gold color of gold occurs due to the relativistic contraction of the 6th of these entities. The occupants of the outermost one of these tend to stay unpaired in the inert pair effect. Their angular wavefunction is a spherical harmonic in which the second parameter is 0 and is equal to one over the square root of four pi. They have a number of radial nodes equal to one less than n, and never have any (*) angular nodes. For the simplest one of them, no nodes pass through the nucleus because its azimuthal quantum number is 0. These constructs overlap to form sigma bonds. They're the first orbitals to completely fill for an energy level. For 10 points, name these spherically symmetric atomic orbitals which can hold two electrons.

s orbitals [prompt on "atomic orbital" or "orbital"; do NOT accept "molecular orbital"]

A quantity represented by this letter symbolizes substituent effects and multiplies rho in the Hammett equation. A German word is the origin of using this letter to represent molecular mirror planes. In collision theory, the sum of the atomic radii, or reaction cross-section, is symbolized by this letter. A chemical company named for this letter merged with (*) Aldrich in 1975. Hydrogen's two frontier orbitals are both labelled by this letter. The head-on collision of either in-phase or out-of-phase orbitals creates molecular orbitals designated by this letter lying along the bonding axis. A triple bond includes exactly one bond designated by this letter. For 10 points, name this Greek letter that names the counterpart to pi bonds.

sigma [or sigma bonds; or sigma orbitals] <Silverman>

6. Antimicrobial nanoparticles of this element turn bacteria into "zombies" that kill other bacteria. This element catalyzes the oxidative syntheses of formaldehyde and ethylene oxide. An electrode containing this element's chloride has largely replaced the calomel electrode in pH meters. This element's nitrate precipitates out halides as cream-colored solids and stains skin and nervous tissue in Golgi's black reaction. This element is the lighter constituent of (*) electrum. This element has the highest thermal and electrical conductivity and is generally in a +1 oxidation state, with a 5s1 4d10 electron configuration, similar to copper, which lies right above it on the periodic table. For 10 points, name this noble metal with symbol Ag.

silver [accept Ag before "Ag"] &lt;Silverman, Science - Chemistry&gt;

High spin complexes with this many d electrons contain four unpaired electrons and are therefore paramagnetic. The superacid with the lowest Hammett function has this many fluorine atoms bound to antimony. Compounds containing chromium with this oxidation state are highly carcinogenic. In nuclear reprocessing, uranium is reacted with chlorine trifluoride to produce a uranium compound with this many (*) fluorine atoms. A molecule with “chair†and “boat†conformations has this many carbon atoms. This is the number of ligands in an octahedral complex. Benzene has this many hydrogen atoms and this many carbon atoms. For 10 points, give this number, the atomic number of carbon.

six or 6 &lt;Hao&gt;

The mnemonic "CLORPT" summarizes Hans Jenny's state equation for these materials' formation. Ammonium acetate extraction is a way to measure the cation exchange capacity of these materials. The composition of these materials distinguishes edaphic communities. Their USDA classification has 12 orders, of which inceptisols and entisols are the most common. If their effective stress is near zero, these materials may undergo (*) liquefaction, as when they are saturated. They form from a parent material through the process of pedogenesis. The profiles of these materials are divided into layers called horizons, and they contain decayed organic matter called humus as well as sand and silt. For 10 points, name these mixtures of weathered rock that support plant life.

soils

These species increase the absorbance wavelength of an analyte in a bathochromic shift. Ionic liquids and deep eutectics are increasingly being used as these species. Green chemists use high-pressure CO2 as one of these species. Ethyl acetate and dichloromethane are used as these species in organic chemistry, which classifies them as protic or aprotic. The chromatographic retardation factor is normalized to the (*) distance traveled by this species. This species is enriched in the raffinate during liquid-liquid extraction. In spectrophotometry, the signal from this species is subtracted out as a blank. This species is removed by recrystallization or is boiled away in a rotovap in most chemical syntheses. For 10 points, name these compounds that dissolve solutes.

solvents &lt;Silverman&gt;

The result of this technique can be predicted by starting from a base value of 214 or 253, and adding multiples of 5 or 30 depending on the structure of the compound. The chlorophyll molecules found in photosystems I and II are named based on the output of this technique. The Woodwardâ€"Fieser (FYE-zer) rules can help interpret the results of this technique, which can yield the (*) A260 (A-two-sixty) over A280 (A-two-eighty) value for DNA. Outside of fluorescent-based techniques, cuvettes (cue-VETS) are exclusively used in this technique. The path length for this technique is denoted b in the equation "A equals e times b times c," which is Beer's law. For 10 points, identify this technique that measures absorption of light between the X-ray and infrared regions.

spectrophotometry [or UV-vis spectroscopy; or ultraviolet-visible light spectroscopy; prompt on optical spectroscopy; do not accept "photospectrometry" or "photospectroscopy"] &lt;Prieto, Science - Chemistry&gt;

Association constants for host-guest complexes are calculated using this technique onBenesi-Hildebrand plots. This procedure is done to aniline derivatives to determine extent ofprotonation using the Hammett acidity function. The Woodward-Feiser rules for this techniqueestimate the influence of conjugated dienes on (*) lambda-max. Samples for it are often placed in glassor fused quartz cuvettes. An equation used in this technique is often expressed as "A = abc", where a is theextinction coefficient, b is the linear path length, and c is the molar concentration. For 10 points, name thistechnique governed by Beer's Law, which measures a compound's absorbance of ultraviolet and visiblelight.

spectrophotometry [or word forms; or using a spectrophotometer; or UV-vis spectroscopy or ultraviolet-visible light spectroscopy before it is read; prompt on it afterwards]

3. The Cheng cycle is used to produce this gas in a cogeneration cycle. Industrial syngas, including most of the world's hydrogen, is synthesized by reacting natural gas with this gas. Superheated, this gas is transported in crimson pipes through the hot side of heat exchangers that run up to 1200 degrees Celsius. This gas displaces the air in the gravity cycle of an autoclave. Psychrometric charts plot the properties of a mix of (*) air and this gas. Today, virtually all Rankine ("RAN-kin") cycles and nuclear power generators use this gas to turn the turbines. This gas can be generated by heating in a Brotan boiler, which was a device that allowed for this substance to drive a namesake kind of locomotive. For 10 points, what gas powered the Industrial Revolution through namesake engines?

steam [or water vapor; or H2O] &lt;Silverman, Science - Engineering and Miscellaneous&gt;

Granules filled with this element are found in Actinomyces israelii. The TPST enzyme isresponsible for adding a group containing this element to tyrosine. A radical on this element is foundin the active site of ribonucleotide reductase. PDI catalyzes the formation of bonds between twoatoms of this element, which in aconitase forms an active site cluster with iron. Its 35 isotope wasused in the Hershey-Chase experiment to label (*) proteins. The chemoautotrophic bacteria living neardeep sea vents use a compound of this element as an energy source. The side chain of cysteine contains thiselement, allowing it to form a type of bridge important in secondary structure stability. For 10 points, namethis element found in thiol groups, with symbol S.

sulfur [or S before mention]

Oxides of this element are found in great leaving groups, like triflates and mesylates. An oxide of this element easily penetrates through nitrile gloves and leaves unsuspecting chemists with the taste of garlic. Iodine oxidizes this element from its +2 state in a common redox titration. Beta-mercaptoethanol reduces this element, unfolding proteins. Purple bacteria oxidize this element, not carbon. Oxides of (*) nitrogen and this element are subscripted with an X. Oxidation of this element crosslinks keratin fibers. This element's dioxide is oxidized by vanadium into oleum in the contact process. It gets oxidized during vulcanization of rubber. For 10 points, name this nonmetal in the same family as oxygen, which normally exists as a yellow solid or a smelly gas.

sulfur [or S]

The ratio of two isotopes of this element is calibrated using troilite from the Canyon Diablo Meteorite.This element's namesake cycle begins with assimilative and dissimilative reduction from organic materialuntil it is re-incorporated into organic matter. The removal of this element from fossil fuels can be donewith the Claus process. A column of superheated water is used to extract this element in the (*) Fraschprocess. It is found bonded to lead in the mineral galena. An acid of this element is often naturally formed byweathering pyrite; along with nitric acid, that acid is the principal component of acid rain. For 10 points, name thiselement that is responsible for the smell of brimstone and whose odor is reminiscent of rotten eggs.

sulfur [or S]

This compound acts as a catalyst in aromatic nitration, and it is typically used along with amercury(II) compound in the hydration of alkynes. This compound is mixed with chromium trioxideand water in the Jones reagent. One industrial process for the production of this compound works byoxidizing a certain element into its trioxide, then converting it into oleum, which is a (*) "fuming"form of this compound. That process uses a vanadium pentoxide catalyst, replaced the earlier lead chamberprocess, and is known as the contact process. This substance has a pKa of around negative 13. Once knownas oil of vitriol and found in battery acid, for 10 points, name this strong diprotic acid with formula H2SO4.

sulfuric acid [or H2SO4 before mention, or oil of vitriol before mention]

Lee and Osheroff investigated a solid phase of this element using a Pomeranchuk cell. This element isthe most common one used to study quantized vortices. New properties of this element were discoveredby Kapitza, Allen, and Misener, all working independently. Two isotopes of this element are continuouslymixed and undergo a spontaneous phase separation in a dilution refrigerator. An isotope of this elementthat is a (*) boson was used by Kamerlingh-Onnes for his most famous discovery. This element is the only one tonever form a solid and standard pressure. Below its lambda point, a form of this element becomes a superfluid,which has zero viscosity. For 10 points, name this element with atomic number two.

superfluid 4-helium [or superfluid 4-He; or "3" in place of "4"]

Griffith's criterion sets the square root of the product of Young's modulus and this quantity for a solid equal to a constant to determine if a material fractures. The pressure differential inside a bubble equals four times this quantity over the radius of the bubble. Electrowetting is used when this quantity is high in order to decrease the contact angle. This quantity equals the increase in Gibbs energy per increase in (*) exposed area. If this quantity is negative, then a liquid in a barometer forms a concave meniscus. This value, which is given in dynes per centimeter and symbolized either sigma or gamma, leads to capillary action. For 10 points, name this quantity which is positive when cohesion is stronger than adhesion, and causes molecules at an interface to cling to each other.

surface tension [or surface energy density]

14. Large values of this quantity drive Ostwald ripening since the critical radius for nucleation scales linearly with it. This quantity is still often reported in multiples of outdated unit ratios involving ergs, dynes, and centimeters. In biochemistry, Triton X-100 is used to reduce this quantity to lyse cells. Three of these quantities, measured in pairs between a solid, a liquid, and a gas, are related by the cosine of the (*) contact angle. Superhydrophobic coatings have ultrahigh values for this quantity. Emulsions and micelles are solubilized by detergents that reduce this quantity. For 10 points, name this quantity, the force required to expand an interface per length, which is high for strongly cohesive liquids like water.

surface tension [or surface energy; or interfacial tension; or interfacial energy] &lt;Silverman, Science - Chemistry&gt;

Titanocene adopts this geometry in Tebbe's reagent. Complexes with this geometry are favoredin metals with low crystal-field splitting energy. Similar to octahedral, complexes of this geometryhave d-orbitals split into two levels, with the t sub two orbitals at higher energy than the e orbitals.Intermediates of this geometry in organic chemistry occur commonly in addition-eliminationreactions before kicking one substituent to form a trigonal planar molecule. (*) S-p-3 hybridizedcarbon has this geometry, which VSEPR theory predicts occurs with one central atom, no lone pairs, andfour substituents. For 10 points, name this molecular geometry which has a characteristic bond angle of109.4 degrees, exhibited by methane.

tetrahedral

On a NFPA diagram, this property of a material is assigned a number in between one and four onthe blue component. Along with metabolism, this property of an NCE is studied before phase 1 ofdevelopment. For most compounds, an absolute form of this property is given by either the LD50 orLC50, the latter of which has the same units as concentration. The therapeutic index is the ratio ofthis quantity for a compound to its (*) benefits. The acute form of this property is measured relative toskin or oral exposure. For a compound, this property can be given in terms of teratogenicity andmutagenicity, the former of which is a measure how likely it is to cause a birth defect. For 10 points, namethis measure of how poisonous a particular substance is.

toxicity [accept word forms; before mention, accept lethality, mutagenicity, teratogenicity, lethal dose, toxic dose, killing dose, poisonous dose etc]

These elements undergo oxidative additions and reductive eliminations. The sum of group number,charge, and the number of covalent and dative bonds is used to count electrons for these elements, andthat number adds up to around 18. The N plus L rule was formulated after observing that some of theseelements lose an electron from their valence shell to half-fill a (*) lower-energy shell. Most heterogeneouscatalysts are composed of these elements. The orbitals of these elements split according to crystal field theory,which explains why solutions of them are often colorful. Lewis bases coordinating these elements form octahedralcomplexes and are called ligands. For 10 points, name these elements with unfilled d orbitals, which occupy thecenter of the Periodic Table.

transition metals [or transition elements; prompt on metals]

Materials that become sediment through changes in this quantity are classified according to theBouma sequence. This property is typically measured with Jackson Units, which uses the visibility ofa flame as a standard of reference. Although it is not transparency, a circle with 2 black and 2 whiteregions is used to measure this property of a fluid - that apparatus is the Secchi Disk. Circulationdriven by this quantity can be induced by (*) soil liquefaction. Adding plankton or runoff to a liquidincreases this quantity, which causes sediment to flow underwater. For 10 points, name this measure of amurkiness of water, typically caused by particles suspended in the liquid.

turbidity [prompt on "currents" due to ambiguities; accept turbidity currents]

This is the number of atoms of carbon plus atoms of oxygen in the ring of the smallest crown ether, and is the first number in its name. Atoms in both hexagonal close-packed and face-centered cubic structures have this coordination number. This is the number of carbon atoms in a lauryl (LAW-rill) group, which can be found in the surfactant (*) SDS. This is the total number of carbons in ethyl-propyl-heptane. The metal with this atomic number is found at the center of chlorophyll; that metal is magnesium. Pentane contains this many hydrogens, which is also the same number of hydrogens in glucose. For 10 points, identify the atomic mass for the most abundant carbon isotope.

twelve [or 12] &lt;Prieto, Science - Chemistry&gt;

The temperatures at which this quantity is the same are linearly related according to Duhring'srule. It is measured using an isoteniscope. The log of this quantity is equal to A minus the quantity Bover C plus T in one equation. This quantity is multiplied by the Poynting correction factor and theactivity coefficient in order to find fugacity. This quantity is graphed against mole fraction in orderto determine (*) deviations from ideality. In general, this quantity equals its value for a pure solvent timesthe mole fraction of the solvent according to Raoult's Law. Volatile substances have a large value for it.This quantity is equal to the atmospheric pressure at the boiling point. For 10 points, name this quantity, thepressure of a gas above a liquid.

vapor pressure [prompt on partial answer; prompt on "volatility"]

Alfred Smee developed a type of these systems which use rough pieces of platinum. John Daniell’s copper (II) (“twoâ€) sulfate model prevented these systems from developing hydrogen bubbles, and secondary examples of these systems use lead sulfate and are reversible. Many (*) citrus fruits can be used as basic examples of these systems, and plating occurs when metallic ions deposit on one electrode in these systems, the two halves of which are connected by a salt bridge. For 10 points, name these electrochemical systems contrasted with electrolytic cells.

voltaic cells [accept galvanic cells; prompt on electrochemical cells or batteries] &lt;AJ&gt;

It's not electrophoresis (electro-for-EE-siss), but running this technique, removing the solvent, rotating the system 90 degrees, and adding a new solvent is this technique's two-dimensional form. A polyhistidine (poly-HISS-tid-een) tag and nickel, or GST and glutathione (gloot-uh-THIGH-own), are common methods of immobilizing biomolecules in the "affinity" version of this technique. Salt concentration is tightly controlled in the ion-exchange form of this technique, and broadening in it is described by the (*) van Deemter equation. A column full of gel is used in this technique’s gel permeation type, while the HPLC (H-P-L-C) type performs it at high pressure. Every technique of this kind has a stationary and a mobile phase. For 10 points, identify this technique that separates mixtures, such as ink on wet paper.

two-dimensional chromatography [or affinity chromatography; or ion-exchange chromatography; or gel permeation chromatography; or high-pressure liquid chromatography; prompt on IEC, GPC, or HPLC] &lt;Prieto, Science - Chemistry&gt;

One technique often performed in this state uses a Buchner funnel to extract a dissolved solid from a solvent. Another technique performed in this state uses a spin bar instead of boiling chips, because that variant does not need to heat the liquid. Water-traps and water aspirators are occasionally used in both the aforementioned namesake filtration and distillation techniques. Experiments carried out in this state usually require Pyrex or round-bottomed glassware because Erlenmeyer flasks or those with (*) cracks may spontaneously collapse. The two walls of a Dewar flask are separated by material in this state, which is often achieved by means of a pump. For 10 points, name this state in which a near-complete lack of vapors leads to extremely low pressure.

vacuum [or more specific answers such as high vacuum or ultra high vacuum; accept vacuum filtration until read; accept vacuum distillation until read; prompt on "low pressure"]

The negative of the partial derivative of the grand canonical ensemble with respect to this quantity gives the average pressure. In the Diesel Cycle, this quantity is held constant during the process that immediately follows isentropic expansion. For a process in which this quantity is held constant, the work done on the system's surroundings is always equal to (*) zero; such a process is represented by a vertical line on an indicator diagram. An isochoric process holds this quantity constant, which is also held constant in Gay-Lussac's Law to illustrate the relationship between a gas's temperature and pressure. For 10 points, name this quantity which changes during thermal expansion, which is abbreviated V.

volume &lt;Jose&gt;

It isn't Ampere's Law, but James Clerk Maxwell corrected instabilities in this equation by adding a horizontal line underneath the saturation dome. A parameter in this equation exactly equals 9/8 times R times critical temperature times critical volume. This equation is directly modified to give the (*) Redlich-Kwong equation. It introduced the hard-sphere model. Solutions to this equation give three roots, including one for liquids and one for vapors. Since it accounts for particle volume and molecular interactions with two parameters labelled a and b, this equation works better than the ideal gas law. For 10 points, name this equation of state whose Dutch namesake also characterized a set of intermolecular attractive forces.

van der Waals equation of state [prompt on cubic equation of state] &lt;Silverman&gt;

For a saturated liquid, this value is approximated using the Rackett equation. Powers of the reciprocal of this quantity are the terms of the virial equation of state. At a constant value of this quantity, the heat capacity of a monatomic ideal gas is equal to n times the ideal gas constant times three-halves. The change in this value in response to a mean stress is given by the compressibility factor. Internal energy plus (*) pressure times this quantity is equal to enthalpy, and isochoric processes keep it constant. This value is inversely proportional to pressure and directly proportional to temperature according to the combined gas law. For 10 points, identify this quantity, the amount of space that an object takes up.

volume [or V]

A compound with this color is the simplest of a class of compounds that react with aldehydes or ketones to form homologated ketones in the Büchnerâ€"Curtiusâ€"Schlotterbeck reaction. That gas, which is this color, also reacts with an acyl chloride in the first step of the Arndtâ€"Eistert synthesis. Besides diazomethane, which is this color, another compound with this color is often used in pulp bleaching. That gas is chlorine dioxide. Despite being poisonous, cadmium sulfide, lead iodide, and lead (*) chromate were all traditionally used as pigments of this color. Bromophenol blue turns this color at pHs below 3, and sodium burns this color in a flame test. The most common allotrope of an element with this color is an eight-atom ring, and aqua regia notably dissolves an element with this color. For 10 points, name this color of elements such as sulfur.

yellow &lt;Hao&gt;

The definition of the acentric factor includes the negative log of the reduced form of this quantity,when the reduced temperature is 0.7. A pure liquid's fugacity is approximated as the product of thefugacity coefficient, the Poynting factor, and this quantity. This quantity is not unitless, but it issmaller for the heavy key component during separations. The logarithm of this quantity varieslinearly with one over temperature by (*) Antoine's equation. At high concentrations, a component'spartial pressure equals its mole fraction times this quantity according to Raoult's Law. It equals atmosphericpressure at the boiling point. For 10 points, name this quantity, the pressure of gas above a solution.

vapor pressure [or saturation pressure; prompt on pressure]

In this technique, overtones are false signals that appear at twice the amount of a very strong signal. Aldehydes are easily identified by this technique due to bumps on the right hand side of the alkane peak. This technique detects stretching and scissoring of bonds in water molecules. Its results are plotted in a wavenumber vs. (*) transmittance graph that typically contains a large peak around 3000 indicating carbon-hydrogen bonds. Solid samples for it can be mixed with potassium bromide and pressed to form a transparent disk. With this technique, every molecule has a unique signature between 500 and 1500 inverse centimeters called the fingerprint region. For 10 points, name this technique that probes samples using light at a wavelength longer than visible light.

infrared spectroscopy [or IR spectroscopy; prompt on spectroscopy] &lt;Prieto&gt;

Dual oxidase proteins were first discovered to produce hydrogen peroxide to help an enzyme oxidize ions of this element. A post-translational modification that adds this element to tyrosine rings initiates a process blocked by drugs such as propylthiouracil (propyl-thio-uracil) and methimazole (meth-imazole). Organification refers to the process of incorporating this element into the body. A solution containing lots of this element traps crystal (*) violet inside cells during Gram staining. TPO adds atoms of this element to thyroglobulin (thy-ro-globulin) in the process of producing T3 and T4. A deficiency of this element can be treated by Lugol's solution and can lead to an enlargement of the thyroid gland. For 10 points, name this halogen whose deficiency can lead to goiter.

iodine [or I; accept iodide or Iâ€" or I-minus] &lt;Ramaswami, Science - Biology&gt;

The reaction that creates "elephant toothpaste" from hydrogen peroxide can be catalyzed by a compound of potassium and this element. In the Cativa and Monsanto catalytic cycles, an intermediate with this element bonded to an acetyl (ah-SEE-till) group reacts with water, kicking off this element and forming acetic acid. Vapor-emitting crystals of this element are used to stain TLC plates brown. Of the (*) diatomic elements, this one is the heaviest. A compound used to nucleate precipitation in clouds is composed of silver and this element, and adding a solution of it to starch turns it black. For 10 points, name this halogen found below bromine, with atomic symbol I (eye).

iodine [or iodide; or I until read] &lt;Prieto, Science - Chemistry&gt;

A ring of atoms of this element was placed on a copper surface by Crommie, Lutz, and Eigler using a scanning tunneling microscope to create a quantum corral. Prussian blue is a complex of this element with cyanide. Its allotropes include austentite, and its 57 isotope is commonly used to demonstrate the Mossbauer effect. The first metallocene contained an atom of it sandwiched between two cyclopentadiene rings. Either ruthenium or this element comprises the most common catalyst for the (*) Haber-Bosch process, and it usually occurs in plus 2 and plus 3 oxidation states, which are known as ferrous and ferric. For 10 points, name this element, alloys of which form steel, with atomic number 26 and symbol Fe.

iron

Bloomeries can purify this element, creating its “sponge†form, cementite. The gamma allotrope of this element is austenite, and it is in both ions forming Prussian Blue. Outside of nickel, this element’s 56 isotope has the highest binding energy of all (*) nuclei. Zinc is applied onto this element’s pure form in galvanization, and the Bessemer process turns the “pig†version of this metal into a strong alloy through adding coke. With ores including hematite and magnetite, for 10 points, name this metal with red rust, the primary component of steel.

iron [accept Fe] &lt;DM&gt;

A common ore of this element consisting of its various oxide-hydroxides is limonite. Shales and chertsalternate with minerals rich in this element in namesake banded formations of Precambrian age. A silicateof this element is fayalite, which is an endmember of the olivine group. This element commonlysubstitutes for magnesium in minerals that are solid solutions, including olivine. Bacteria that oxidize thiselement, such as Gallionella, are a common fouling organism in wells and create a (*) reddish-brown ororange-ish slime. The inner core consists primarily of nickel and this element. A sulfide of this element is pyrite andits most common ore is hematite. For 10 points, name this common magnetic metal in the Earth's crust, which haschemical symbol Fe.

iron [or Fe until it is read]