CHEM misses

0 has oxidation of what when connected to nonmetal?

+1

H has oxidation # of what when connected to nonmetal?

-1

what is bonding configuration of phosphine PH3?

1 LP, 3 bonds to H

How many sodium ions are in the initial 50.00-mL solution of Na2CO3? A 6.57-g sample of NiSO4•6H2O (molar mass 262.84)

3.00 × 10^22 first find moles Na2CO3, then multiply x2 bc 2 moles Na, the x #ions/mol

Atrial fibrillation is the most common heart arrhythmia, causing palpitations, fainting and chest pain. According to the information in the passage, what is most likely to be observed in the ECG during atrial fibrillation? A. Missing P waves and an irregular rate B. Complete absence of P waves and a regular rate C. Complete absence of R waves and an irregular rate D. Missing R waves and a regular rate

A -

Which of the following types of electromagnetic radiation would have the shortest wavelength? A. Radiation that ejects an electron from an sp orbital B. Radiation that ejects an electron from an sp2 orbital C. Radiation that ejects an electron from an sp3 orbital D. Radiation that excites but does not eject an electron from an sp3 orbital

A - MORE sp character = closer to nucleus = higher energy

Which of the following best explains why arginine is more basic than lysine? A. The electron-donating groups around the basic nitrogen on arginine make its conjugate base less stable .B. The electron-donating groups around the basic nitrogen on arginine make its conjugate acid more stable. C. The lack of electron-donating groups on lysine make its conjugate acid more stable. D. The lack of electron-withdrawing groups on lysine make its conjugate base more stable.

A - more stable Conjugate acid = stronger base

Al(OH)3(aq) + NaOH(aq) → Na[Al(OH)4](aq In the reaction shown in Equation 1, Al(OH)3 acts as what kind of acid or base? Lewis acid Lewis base Brønsted acid Brønsted base

A! because accepting electron pair (OH)

As an alternative to the industrial preparation outlined by Reactions 1 and 2, potassium permanganate can be prepared in the lab by each of the reactions shown below. All of these can be classified as a disproportionation reaction EXCEPT: I. 2 K2MnO4 + Cl2 → 2 KMnO4 + 2 KCl II. 3 K2MnO4 + 4 HCl → 2 KMnO4 + MnO2 + 2 H2O + 4 KCl 3 K2MnO4 + III. 2 CO2 → 2 KMnO4 + 2 K2CO3 + MnO2 A.I only[ B.III only[ C.I and II only D.II and III only

A! same species is oxidized and reduced in disport.

Which of the following may hold true of a compound if an increase in pH of the solvent results in increased solubility of the compound? A. The compound is an acid B. The compound is a base C. The compound contains an ionic bond D. The compound has charge at neutral pH

A. if increasing pH improves solubility than likely because it removes proton, allowing molecule to become charged .

2 Ag(s) + H2S(aq) → Ag2S(s) + H2(g) what is the reducing agent?

Ag! because it is oxidized

Efforts to treat lactic acid buildup in muscles were attempted using dissected muscle specimens in the laboratory. One of these experiments involved ammonium formation from dissolved ammonia. Under conditions of excessive lactic acid: A. the final concentration of ammonium will be higher than otherwise due to higher pH. B. the final concentration of ammonium will be higher than otherwise due to lower pH. C. the final concentration of ammonium will be lower than otherwise due to higher pH. D. the final concentration of ammonium will be lower than otherwise due to lower pH.

B - d.t. more H+ions

Na2CO3 + HCl → CO2 + H2O + NaCl Consider the above unbalanced equation. For this reaction, how many mL of a 2 M solution of Na2CO3 are required to produce 11.2 L of CO2 at STP? A. 125 mL B. 250 mL C. 375 mL D. 500 mL

B - set up stoichiometry starting with CO2

What is the molar concentration of Na+(aq) in a solution that is prepared by mixing 10 mL of a 0.010 M NaHCO3(aq) solution with 10 mL of a 0.010 M Na2CO3(aq) solution? 0.010 mole/L 0.015 mole/L 0.020 mole/L 0.030 mole/L

B - when equal volumes mixed, must add both molar quant. and divide by 2

A researcher constructs a hypothetical reaction that follows a mechanism that uses the two reactions below: 3 Q2 + 2 AX4 → 2AX3Q + 2XQ + 2Q- 1. AX3+ Q2→ AX3Q + Q- 2. 2 AX4 + Q2 → AX3Q + Q- If the second reaction is experimentally determined to be an order of magnitude slower than the first reaction, the researcher can likely conclude that the rate law followed by the hypothetical reaction would be which of the following? A) R = k[AX4][Q2] B) R = k [AX4]2[Q2] C) R = k [AX4]2[Q2]2 D) R = k [AX4]2[Q2]3

B BC remember: slow step determines rate law, and coefficients become eponents!

If the solubility of sodium acetylsalicylate is roughly 120 g per 100 mL of water, what is the approximate molar concentration of the saturated NaC9H7O4 solution used in the reaction? acetylsalicylate (molar mass = 202.2) A.0.006 mol/L B.0.59 mol/L[ C.5.9 mol/L D.1,200 mol/L

B.

Humins are large, complex organic molecules found in soil that remain insoluble after treatment with dilute alkaline solutions. Which of the following functional groups do humins most likely lack? A.Esters BCarboxylic Acids' CAlcohols' DCarbonyls

B. bc if they had these base would deprotenate, increasing solubility!!

What is the relationship of these molecules to each other? A. Meso compounds B. Enantiomers C. Diastereomers D. Same compound

B. to know if same compound, MUST look at R/S config!

Based on the information in the passage, what is the mass of calcium (MW = 40.1 g/mol) in Sample 1 after dilution? (sample is 50 mL of .005 M) A.0.003 g B.0.005 g C.0.01 g D.10 g[

C

What is the molarity of cinoxate (0.250 kg/mol) in 100 mL of sunscreen B16 (density = 1 g/mL)? A.100 M[ B.0.0010 M C.1.0 M[ D.1000 M

C

Heat is transferred throughout the body as a result of warm blood flowing past the cells that line capillary walls. This type of heat transfer is an example of: A. radiation. B. convection. C. conduction. D. condensation

C - Causes individual cells to bump into each other which raises their Temp, vibrations repeated as vibrations pass through cell to surrounding tissues

Magnesium halides are present in human blood at a concentration of approximately 0.10 mM. What is the expected concentration of halide ions in the typical human blood sample? A. 0.010 mM B. 0.10 mM C. 0.20 mM D. 0.30 mM

C bc MgH requires 2 halides so use i rule!

how to get from M to mg/dL when answers are in M? Normal blood calcium concentration is between 2.18 mM and 2.60 mM. Which of the following calcium concentrations would be considered normal blood calcium? A. 10 mg/L B. 50 mg/L C. 100 mg/L D. 1000 mg/L

C! work backwards - Divide conc in M by molar mass to get new moles. NO NEED to take L into account bc Moles has L already in it! EASIER TO WORK BACKWARDS .1 g/40 g/mol = 2.5 x 10-3 moles

What volume of the copper(II) sulfate solution (MM=159.6, .5 M) should be used in the reaction to deliver 0.8 g of CuSO4 into the reaction mixture? sodium acetylsalicylate (molar mass = 202.2) A.1.6 m B.2.5 mL[ C.0.01 L[ D.0.40 L

C. AGAIN, when given volume, must first convert to molar conc. we only care about volume of the sodium acetylsalicylate, so only need to use that mm and molarity .8g/1.6x10^2 g/mol =.5x10^-2 mol .5M*xL = .5x10^-2 mol, .01 L OR .5x10^-2 mol/.5 M/L = .1x10^-2 mol

Suppose that CH4(g) reacts completely with O2(g) to form CO2(g) and H2O(g) with a total pressure of 1.2 torr. What is the partial pressure of H2O(g)? 0.4 torr 0.6 torr 0.8 torr 1.2 torr

C. must write balanced eq'n first and see that1 CO2 produced: 2 H20 so mol fraction CO2 product 2/3* 1.2 = .8

What is the energy content in kcal of one peanut, if the temperature of 1 kg of water in a calorimeter increases by 50oC upon the combustion of 10 peanuts? 0.5 kcal 1 kcal 5 kcal 10 kcal

CANCEL EVERYTHING1!!!

Examining the results in Figure 2, the common ion effect accounts for: I. the increased yellow precipitate observed in Figure 2 when AgNO3 is added. II. the increased yellow precipitate observed in Figure 2 when K3PO4 is added. III. the decreased yellow precipitate observed in Figure 2 when Ba(OH)2 is added. A. I only B. II only C. III only D. I and II only

D - CI effect would always, ONLY cause increased precipitate

Which of the following types of proteins would be most efficiently fractionated by an SEC column? A. Two proteins with very high molecular weights B. Two proteins with similar molecular weights C. Two proteins with very low molecular weights D. Two proteins with substantially different molecular weights

D - as long as proteins fall within column's exclusion limits, it's best to use those with most different MWs possible for most efficient separation

When a model bone segment is pushed horizontally across a model bone surface at constant speed, the work required to move the model bone segment is converted to: A. potential energy. B. kinetic energy. C. chemical energy. D. thermal energy.

D - bc when two surfaces slide past one another under friction, the energy (work) required to move the object is converted to TE

Which statement correctly describes both the 3s and 3p energy levels in the lowest-energy electron configuration of the phosphide anion P3− ? A.Both the 3s and 3p levels are half-filled B.The 3s level is filled and the 3p level is half-filled. C.The 3s level is half-filled and the 3p level is filled D.Both the 3s and 3p levels are filled

D bc 3-

The solubility of Mg(OH)2 is equal to z. Which expression is equal to the solubility product for Mg(OH)2? A. z2 B. z3 C. 2z3 D. 4z3

D! for every 1 Mg there are 2OH, so x(2x)^2 = 4x^3

Which of the following particles is expected to have the LEAST mass? A. An alpha particle B. A beta particle C. A positron D. A gamma particle

D! photons are massless! gama rays are a form of electromagnetic radiation

What approximate volume of the oxytocin solution with the 10 mM Zn2+ additive was analyzed if 2.2 × 10−6 moles of oxytocin acetate (MW = 1067 g/mol) were recovered from the sample after 4 weeks at 50 °C? (note: conc. is .3 mg/mL,and 80% oxytocin recovery at this conc!) A.9 μL B.900 μL C.2 mL D.10 mL

D. 1. 2.2 × 10−6 moles recovered/.8moles recovered=2.75 m, 2. 2.75 × 10−6 m*1067 g/mol=~2.910^-3 mol 2.9 mg/.30 mg ~ 10 mL

The precipitation of salts can be improved with which of the following steps? A. Increasing the temperature B. Adding more water to the solution C. Decreasing the pressure over the solution D. Adding ethanol to the solution

D. because organic solvents cannot dissolve salts!!!

LARGER Ksp means ________ dissolution and _______ precipitate

MORE, LESS

What is the maximum volume of PH3(g) that a chemist can obtain from the reaction shown by Equation 1a, if 0.005 mol LiPH2 reacts with 0.002 mol R2NBCl2 at 0oC and 1 atm? 0.672 mL 6.72 mL 67.2 mL 67.2 L

NO NEED TO FIND LR HERE BC YOU KNOW HOW MANY MOLES WILLFORM FROM EQ'N!!! just see .03 M PH3 formed >.003x22.4

What are atoms metalloids?

Si Ge As Sb Te At

What explains this trend?

Zeff.

P wave is contraction of the ______ QRS is contraction of the _______ SA node is located in ________ ventricular contraction occurs d.t. ______

atria QRS right atrium depolarization

compensatory method for respiratory acidosis is ________ and consuming more ________

breathing faster, decreases CO2 and consumes more H+!

chelate formation vs redox reaction?

chelate form. is when metal cation and ligand react to form one or more rings

name for when a substance undergoes rxn to form to or more substances

decomposition

Researchers further analyzed HA by obtaining a gas chromatography spectrum. This process involves the vaporizing of HA to form a gas. Which equation can be used to predict the density ρ of the HA gas, using the molecular weight (MW) of HA? rearrange ideal gas law to solve for density given MW

density = P*MW/RT

When comparing atoms across the same row of the periodic table, which group will contain the atom with the lowest second ionization energy?

group 2!

KmNO4 and Oso4 does what?

oxidizes DBs and OsO4 to alcohols

Using the table below, which solution would be best suited recrystallization of benzoic acid? A. Solvent X B. Water (pH 7) C. Water (pH 12) D. The answer cannot be determined with the given information.

rechrystallization calls for a solvent that is in which the solute is only mildly soluble (soluble at high T, insoluble at low T)

A given atom's emission spectrum may appear to be lower E/higher WL than the excitation spectrum bc

there is a loss of vibrational energy when electrons move from excited to ground state

make ice chart. know conc. F added is .2, so .2+2x is about .2. then use Ksp expression for CuF^2 Ksp = x[2(x)^2] x(.2)^2 = .04x 1.6x10^-6 =.04x

x = 4x10^-5