C/P NextStep MCAT PT #3

What is a carboxylic acid?

-COOH

What is a ester?

-COOR'

The visible spectrum contains electromagnetic signals with wavelengths ranging from ___ to ____ and visible to the human eye?

400 to 700 nm

During strenuous exercise, lactic acid buildup in cells causes the creation of a hydronium complex known as the Eigen cation (H9O4+). If water molecules then experience hydrogen bond attractions to the Eigen cation, this attractive force: A. results in a semi-stable shell of water molecules around the hydronium. B. results in an inability of hydronium to be neutralized by bases the way normal H+ ions would be. C. results in the ability of muscle cells to reverse both the hydronium creation process and the lactic acid creation process once sufficient oxygen is once again made available. D. results in mobility of hydronium within the environment surpassing the mobility of regular water molecules.

A is correct. A process known as "hydration" or "solvation" occurs when the attractive force of an ion molecule causes a thin shell of water molecules to surround it. In the case of hydronium (H3O+), each of the H atoms attracts the O atom in an H2O molecule due to hydrogen bonding. These H2O molecules cause a "shell" of water molecules to surround the hydronium.

Which of the following is a weak acid in aqueous solution? A. HF B. HCl C. HBr D. HI

A is correct. All but one of the hydrohalic acids completely dissociate. The one exception is hydrofluoric acid, which is a weak acid in aqueous solution due to its unusually high degree of covalent bonding between the fluorine and the hydrogen.

If a modern portable defibrillator uses as 12 V battery and a 20 μF capacitor, what is the total charge stored on the plates of the capacitor? A. 0.24 mC B. 24 mC C. 24 C D. 60 C

A is correct. Capacitance (C, measured in farads) is the amount of charge stored per volt, expressed with the equation C = q/V. This means that charge (q) = VC. (Do you remember the home shopping network, QVC?) The capacitance is given as 20 x 10-6 F. Substituting the voltage (12 V) and capacitance into the equation gives us the charge (in coulombs). (20 x 10-6 F)(1.2 x 101 V) = 24 x 10-5 C = 2.4 x 10-4 C = 0.24 x 10-3 C = 0.24 mC

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 is correct. This question asks us about the wavelength of EMR that ejects an electron from an atom. Shorter-wavelength EMR (such as γ rays) carries much more energy than longer-wavelength EMR (such as radio waves). Therefore, we must look for the answer choice that involves the highest-energy EMR. The closer an electron is to the nucleus, the harder it is to eject. Because sp-hybridized orbitals have the most s character of all of the answer choices, they contain the electrons that are hardest to eject.

The electrical resistance of dry skin is 100 kΩ, but can be lowered to 20 Ω if electrode contact area is large and conducting gel is used on the skin. If Vmax of the defibrillatror 500 V and lasts 0.01 s, what is the maximum possible current delivered to the heart during defibrillation? A. 2.5 × 101 A B. 2.5 × 10-2 A C. 5.0 × 10-2 A D. 5 A

A is correct. We are given R, V, and time, and the question asked us to determine current (charge/time, or C/s). We do not need to use the time since we should know Ohm's law, V = IR. If I = V/R and the question asks for the maximum current, we should use the smallest available resistance. I = V/R = (500 V) / (20 Ω) = (50) / (2) = 25 amps = 2.5 × 101 A

SN1 reaction

An SN1 reaction proceeds by way of a mechanism in which the leaving group (in this case, a chloride) dissociates in a kinetically slow step, producing a planar carbocation which is then rapidly attacked by a nucleophile.

How much heat is produced from the complete combustion of 30.0 g of methane, if the enthalpy of reaction is -890 kJ/mol? A. 1.7 x 103 J B. 1.7 x 106 J C. 4.7 x 106 J D. 4.7 x 109 J

B is correct. First, note that methane has a molecular formula of CH4. Thus, its molecular weight is approximately 12 + 4(1) = 16 g/mol. 30 g CH4 x (1 mol/16 g) x (890 kJ/mol) = 1.8 x 103 kJ (if we round 890 to 900 kJ/mol) Note that the answer options have units of joules (J), not kilojoules (kJ), and choice A should be eliminated. Converting the units gives: 1.8 x 103 kJ x (103 J /1 kJ) = 1.8 x 106 J

The results of a separate study of the thermodynamic parameters for the interactions of proteins with cyclohexanol and quartenary ammonium salts indicate that the hydrophobic solute-solute interaction is spontaneous, and that ΔH and ΔG have opposite signs. Which of the following must be true for this interaction when temperature is a positive value? I. ΔH > ΔG II. 0 < ΔS III. ΔH < ΔS A. I only B. I and II only C. II and III only D. I, II, and III

B is correct. For the interaction to be spontaneous, the free energy change of the reaction must be negative. The question states that the enthalpy and free energy changes for the interaction have opposite signs. Thus, ΔG is negative and ΔH is positive, making Roman numeral I true. For a reaction to be both endothermic (positive ΔH) and spontaneous (negative ΔG), the reaction must involve an increase in entropy (ΔS is positive). This is according to the equation: ΔG = ΔH - TΔS. Thus, II is also true because ΔS is positive.

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 is correct. In an acidic environment, a base such as ammonia (NH3) will dissolve into its conjugate acid, ammonium (NH4+), to a greater extent than would have been the case in a neutral or a basic environment. An environment with lower pH is an environment that is more acidic.

A 60-kg runner raises his center of mass approximately 0.5 m with each step. Although his leg muscles act as a spring, recapturing the energy each time his feet touch down, there's an average 10% loss with each compression. What must the runner's additional power output be to account for just this loss, if he averages 0.8 s per stride? A. 0 W B. 37 W C. 46 W D. 331 W

B is correct. This is a multi-step question, though each step is relatively straightforward. The gravitational potential energy at the runner's height is: PE = (60 kg)(10 m/s2)(0.5 m) = 300 J Most of this energy is conserved as the runner hits the ground and his muscles capture the energy as spring potential energy, so the question only asks about the lost energy, amounting to 10%, or 30 J. Don't worry about the mechanics of which foot lands first and how much of the kinetic energy each one absorbs. The question stem doesn't give that kind of information, so there's nothing for it anyway. So, an additional 30 J is needed per stride, and a stride occurs every 0.8 s. Thus: P = (30 J)/(0.8 s) = 40 W This is between answer choices B and C. So is it really 40 W? Well, no, 8 goes into 30 less than 4 times, so the answer should be lower. Also, g is closer to 9.8 than 10, so that also caused the value of energy, used in the power calculation, to be overestimated. 37 W, then, must be the match.

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.

B is correct. This question is asking us to determine why arginine is more basic than lysine. The reason must be related to how arginine is better able to handle being protonated, as this is the essence of being a base. Since, in its protonated form, arginine has electron-donating groups via resonance with other nitrogens, it is a more stable conjugate acid. The resonance structures of arginine at this position are shown below. Note that the backbone amino and carboxylic acid groups are deprotonated, meaning that this is the structure of arginine at relatively high pH (albeit not high enough to deprotonate the side chain).

A student determined that her yield of aspirin was 3.9 g. What was her percent yield? D= 1.08 g/m3; 5g salicylic acid; MW 180 g/mol A. 45% B. 60% C. 78% D. 92%

B is correct. We first need to determine if there is a limiting reagent and then determine the theoretical yield. The moles of acetic anhydride can be determined by using the volume and density information 7 mL x 1.08 g/mL x 1 mol/102 g ~ 7 x 10-2 mol calculate the moles of salicylic acid: 5.0 g x 1mol/138 g ~ (5/1.4) x 10-2 ~ 3.5 x 10-2 mol 1:1 from Reaction 1, the acetic anhydride is in excess and the limiting reagent is the salicylic acid. theoretical yield can be calculated using the molecular weight 3.5 x 10-2 mol x 180 g/mol ~ 3.5 x 2 x 10-2 x 102 ~ 7 g Since the question indicates that the actual yield was 3.9 g, which is about 4 g, the percent yield is (4/7) x 100 ~ 60%.

What is the pH of a 0.10 M aqueous solution of acetylsalicylic acid? A. 1.0 B. 2.3 C. 3.5 D. 4.1

B. Ka = [H+][A-]/[HA] 10-3.5 = x2/(0.1-x) **Since x will be small, we can approximate 0.1-x ~ 0.1, giving: 10-3.5 = x2/(0.1) 10-3.5(0.1) = x 2 10-4.5 = x2 [10-2.25][10-2.25] = x2 10-2.25 = x Since x equals the hydrogen ion concentration, taking the -log(10-2.25) = 2.25.

If a 3-kg rabbit's leg muscles act as imperfectly elastic springs, how much energy will they hold if the rabbit lands from a height of 0.5 m and its legs are compressed by 0.2 m? A. -0.6 J B. 0 J C. 13 J D. 14.7 J

C is correct. Potential energy of the rabbit at the peak of its height is PE = (3)(10)(0.5) = 15 J, or, if we're more exact and use 9.81 for g, slightly less than that. 14.7 J seems about right. 13 J is clearly a little on the low side, but this is exactly what's needed for this question, since the question stem is dropping a big hint that some energy is lost.

What is the standard cell potential for the starch battery created? (Galvanic cell --? spontaneous) A. -1.136 V B. -0.916 V C. 0.916 V D. 1.136 V Given: NAD+ (Ered= -0.32V) to NADH; AQDS electron carrier (Ered=-0.10); Reduce O2 (Ered=0.816V) to H2O

C is correct. Since galvanic cells always have cell potentials that are greater than 0, we can eliminate any negative options . Paragraph 1 gives E°reduction of O2 as 0.816 V and E°reduction of AQDS as -0.10 V. Since both species cannot reduce at once, we must reverse the sign of one of the reduction potentials to find the oxidation potential. For galvanic cells, reverse the less positive reduction potential, which is -0.10 V here. The associated oxidation potential, then, is +0.10 V. Finally, since we now have a reduction and an oxidation, we can simply add the values directly to yield 0.816 V + 0.10 V = 0.916 V.

Students fractionating two proteins of unequal molecular weight noted that the proteins eluted from the SEC column simultaneously. Which of the following statements best explains this observation? A. The shape of a molecule is unrelated to its rate of migration. B. One of the proteins has a molecular weight beneath the exclusion limit. C. The molecular weight of both proteins exceeds the exclusion limit. D. Both proteins possess equal charge at the buffered pH.

C is correct. According to paragraph 4, the stationary phase exerts a retarding effect only against those proteins with molecular weight between the inclusion and exclusion limits of the column. Because differences in the rate of migration through the column are a function of size exclusion arising from that retarding effect, it would be expected that two proteins with a molecular weight exceeding the exclusion limit of the column would elute simultaneously.

When does a runner output the most additional energy to keep the ground reaction forces most nearly vertical and through her body's center of mass? A. When she takes high, bouncing strides and keeps her spine fairly vertical B. When she takes long, low strides and keeps her spine fairly vertical C. When she takes high, bouncing strides and leans her upper half into her run D. When she takes long, low strides and leans her upper half into her run

C is correct. Both the vertical displacement of the runner's steps and the angle of her body from the vertical increase the energy required to realign the ground reaction forces. Recall that tanθ = sinθ/cosθ, so when θ is close to zero, so is tanθ. When θ is close to 90°, tanθ becomes arbitrarily large. The more the runner leans into the run, the greater (or closer to 90°) tanθ is, and the greater the work expended by the runner must be, according to the work equation given in the passage (Wx = Fz tan(θ) Δz). Also, in this equation, the passage states that Δz represents the vertical displacement of a single step. Thus, the higher the vertical displacement ("high, bouncing strides..."), the greater the energy expenditure.

A balloon has a volume of 3.0 L at 25°C. What is the approximate volume of the balloon at 50°C? A. 1.5 L B. 2.0 L C. 3.3 L D. 6.0 L

C is correct. Charles' law states that there is a direct relationship between the volume of an ideal gas and its temperature, when pressure is constant. Note that the temperature must be in Kelvin! We can approximate the initial temperature as 300 K and the final temperature as 320 K. (3.0 L)/(300 K) = V2/(320 K) [(3.0)(320)] / (300) = (3.0)(1.1) = 3.3 L

Underproduction of pulmonary surfactant in IRDS leads to decreased compliance of alveolar tissue. Based upon this information, which of the following must be true regarding pulmonary surfactant? A. Its adsorption to the water-alveolar interface increases surface tension, preventing alveolar collapse due to intra-thoracic pressure. B. Its absence decreases the minimum radial size of alveoli able to avoid collapse at a given pressure of inspired air. C. Its adsorption to the water-alveolar interface decreases surface tension, decreasing the pressure difference required to inflate the airway. D. Its presence increases the efficiency of gas exchange across the alveolar membrane by decreasing the surface area of the alveolus at a given pressure of inspired air.

C is correct. During inspiration, contraction of the diaphragm and external intercostal muscles leads to expansion of the thoracic cavity and a decrease in intrapleural pressure. This negative pressure, relative to atmospheric pressure at the entry of the upper airway, generates airflow through the respiratory tree and to its terminal extension—the alveoli. The elastic recoil force of the airway and the surface tension of the water lining the airway oppose expansion of the alveoli due to the influx of atmospheric pressure. Pulmonary surfactant adsorbs to the air-water-alveoli interface, reducing surface tension and the total force resisting expansion. This increases pulmonary compliance—a measure of lung volume change at a given pressure of inspired air—and decreases the work required to expand the lungs at a given atmospheric pressure. This is consistent with choice C.

Y32 is pH-sensitive. This can be a problem when employing it to monitor changes in the energy balance of a cell because: A. pH can differ between cells. B. the ATP-to-ADP ratio of a cell depends on pH. C. pH may change over time in the same cell. D. decreased pH favors the CPV B-state.

C is correct. If the biosensor is pH-sensitive, then changes in cellular pH over the course of a measurement could confuse changes in the energy balance of the cell, as reflected by the cell's ATP-to-ADP ratio.

Which of the following electronic transitions for hydrogen would result in the emission of a quantized amount of energy? A. n = 1 → n = 2 B. n = 2 → n = 3 C. n = 5 → n = 4 D. n = 4 → n = 6

C is correct. In order to emit a photon carrying energy, an electron must go from a higher energy level to a lower energy level. Only choice C shows such a transition.

If a scientist chooses not to employ a SEC column, but wishes to fractionate a protein sample on the basis of only molecular weight, what technique would be most appropriate? A. Affinity chromatography B. Ion-exchange chromatography C. SDS-PAGE D. NMR spectroscopy

C is correct. SDS-PAGE is an electrophoretic technique which involves the binding of the anionic detergent SDS to a polypeptide chain. SDS binding denatures and imparts an even distribution of charge per unit mass to the protein, resulting in fractionation by approximate size alone during electrophoresis.

Phosphorous acid, a common ingredient used for potable water treatment, has a molecular formula of: A. H3PO5 B. H3PO4 C. H3PO3 D. H3PO2

C is correct. The anion in phosphorous acid is phosphite, PO33-. When comparing the -ous acids and -ic acids, the -ous acids will have 1 fewer oxygen atoms than their -ic counterparts. A: This is perphosphoric acid. B: This is phosphoric acid. D: This is hypophosphorous acid.

How many liters of carbon dioxide at STP are produced by reacting 100 g of calcium carbonate with an excess of hydrochloric acid? A. 0.0 L B. 11.2 L C. 22.4 L D. 44.8 L

C is correct. The balanced chemical reaction is: CaCO3 (s) + 2 HCl (aq) → CO2 (g) + H2O (l) + CaCl2 (aq) From the periodic table, the formula weight of calcium carbonate is 40 + 12 + 3(16) = 100 g/mol. 100 g of calcium carbonate therefore represents one mole, and based on the reaction, this will produce one mole of carbon dioxide gas. Remember, one mole of any gas at STP (standard temperature and pressure) has a volume of 22.4 L! Thus, the volume of gas produced will be 22.4 L at STP. 100 g CaCO3 x 1 mol/100 g x 1 CO2/1 CaCO3 x 22.4 L/mol = 22.4 L CO2

Figure 1 shows a drop in the first ionization energy in going from beryllium to boron. Which of the following best explains the source of this drop? A. Boron contains one valence electron, while beryllium contains none. B. After putting two electrons in the valence s-type subshell for beryllium, the third valence electron for boron must enter an orbital that already contains an electron of opposite spin. C. The two valence electrons for ground state beryllium are in an orbital with an azimuthal quantum number of l = 0, whereas the third valence electron in ground state boron must be in an orbital with an azimuthal quantum number of l = 1. D. The two valence electrons for ground state beryllium are in an orbital with a magnetic quantum number of m = +1, whereas the third valence electron in ground state boron must be in an orbital with a magnetic quantum number of m = -1.

C is correct. The electron configuration for beryllium is 1s22s2. The azimuthal quantum number for an s-type orbital is l = 0, which defines the shape of the electron cloud (a spherically-shaped electron wave, with no nodes). For boron, since the s-type orbital in the valence shell cannot hold more than two electrons, the third valence electron must be placed into a p-type orbital, giving an electron configuration of 1s22s22p1. The azimuthal quantum number for a p-type orbital is l = 1 (a dumbbell-shaped electron wave with one node at the nucleus). The 2p orbital is slightly higher in energy than the 2s orbital, making it slightly easier to ionize this electron. Choice C is the only answer option that correctly describes this situation. The shapes of the s-type and p-type orbitals are shown below. (Note that multiple possible shapes exist for p-type orbitals.)

What is the difference between D&L and R&S?

D and L simply describe the direction in which polarized light is rotated by the molecule. -It applies to the molecule as a whole, but gives you absolutely no specific info. -In other words, "D" and "L" cannot tell you if a substituent is "going forward" or "going backward" in any way. R and S give you specific information about position of groups on a chiral center. -If you know something is in the R configuration, you know how to specifically position the groups around a chiral center in 3-dimensions. - you cannot assume if this positioning will rotate light in D or L directions.

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 is correct. A gamma particle is a photon of electromagnetic energy, which does not have mass.

In the presence of a carbohydrate, which of the following statements regarding the enthalpy and entropy of the gel-to-liquid-crystal transition in DPPC is true? A. The entropy of transition decreases, while the enthalpy of transition increases. B. The entropy of transition increases, while the enthalpy of transition decreases. C. Both the entropy and the enthalpy of transition increase. D. Both the entropy and the enthalpy of transition decrease.

D is correct. According to the experimental data summarized in Table 1, addition of any carbohydrate leads to an entropy change, ΔS, for the phase transition of an aqueous dispersion of DPPC that is smaller than the entropy change in the absence of a carbohydrate (7.22 cal/K•mol).

If a flat Petri dish containing a single layer of cells suspended in viscous culture medium is tapped, some cells will collide into each other. If cell 1 collides into cell 2 on such a plate, which of the following describes what happens to cell 2 after the collision, assuming an elastic collision and non-zero drag from the medium? I. Cell 2 continuously accelerates. II. Cell 2 moves with decreasing speed. III. Cell 2 moves with constant speed. IV. Cell 2 decelerates until it reaches a velocity of 0 m/s. A. I only B. II only C. III only D. II and IV only

D is correct. Cell 2 can only accelerate while it is being pushed/in contact with cell 1, so statement I is false. Since the cells experience drag from the medium, cell 2 will decelerate after the collision, making statement II correct and statement III incorrect. The drag will cause cell 2 to continuously decelerate until it comes to rest.

What is the net charge on a phenylalanine molecule at pH 1? A. -1 B. 0 C. +0.5 D. +1

D is correct. T Being an amino acid, phenylalanine has an acidic carboxy group that will be protonated at a pH of 1 (remember, such a pH is highly acidic). Additionally, it has a basic amino group that will also be protonated. Finally, it contains a neutral toluene side chain. In total, the charge will be (0 from the carboxy group) + (+1 from the amino group) + (0 from the side chain) = +1. The image below depicts phenylalanine at this pH.

Which of the following alkyl chlorides is most likely to undergo an SN1-type reaction? A. Chloromethane B. Chloroethane C. 2-chloropropane D. 2-chloro-2-methylpropane

D is correct. The compound mentioned in choice D is alternatively termed tert-butyl chloride (below). Steric congestion tends to promote SN1-type mechanisms, so a tertiary alkyl halide, like tert-butyl chloride, would favor pushing the leaving group off to form the carbocation.

Free radicals from ionizing radiation are highly unstable and have carcinogenic effects. These effects are most likely result from damage to: A. proteins. B. phospholipids. C. the Golgi apparatus. D. nucleic acids.

D is correct. The question stem states that free radicals can cause cancer, which is a result of poorly regulated cell growth and division. Cancer is generally a product of mutations in DNA that disrupt these processes. Therefore, we must choose the answer that targets DNA, which is choice D.

An artificial leg designed for use by runners is spring-based, to mimic the compression required of a muscle during hard running. For safety reasons, it was determined that the leg should be able to absorb as much as 125 J of kinetic energy without compressing more than 10 cm, or the runner would be likely to stumble. What should the spring constant be? A. 250 N/m B. 2,500 N/m C. 12,500 N/m D. 25,000 N/m

D is correct. When the leg "absorbs" kinetic energy, it is converted to elastic potential energy. While this process involves the loss of some energy as heat, we can assume that it is a perfectly elastic process here for the sake of simplicity. Thus, the leg needs to hold up to 125 J of elastic PE. The formula for potential energy contained in a spring is PE = (1/2) kx2. Since PE and KE are interconverted as the individual runs, we can write this formula as KE = (1/2) kx2, which can be rearranged to yield k = 2 KE/x2. k = (2)(125 J) / (0.10 m)2 k = (250 J) / (.01 m2) k = 25,000 N/m

The greatest amount of glucose is produced when enzymes with a ____ current and ___ absorbance is used.to break polysaccharides

High current, Low absorbance. Greatest breakdown of starch

What is an amine?

Nitrogen bonded to 3 other groups (can be R groups or H

atrial fibrillation from heart arrhythmias, palpitations and fainting will have what observation on a ECG reading?

On a PQRS wave, . complete absence of R waves and an irregular rate

What happens during the P wave?

P wave is depolarization and contraction of the atria. A rest potential is created when sodium ions are pumped to the outside surface of the membrane of a cell. When ion channels open, the sodium ions spontaneously flow back into the cell, resulting in depolarization and an action potential.

Which regions of Figure 1 are most likely to be explained by the movement of sodium ions into a cardiac neuron? I. P II. Q III. R IV. T A. P only B. Q and R only C. P, Q, and R only D. P, Q, R, and S

P, Q, R waves has movements with Na+ P wave is depolarization and contraction of the atria. A rest potential is created when sodium ions are pumped to the outside surface of the membrane of a cell. When ion channels open, the sodium ions spontaneously flow back into the cell, resulting in depolarization and an action potential. Q and R waves is contraction of the ventricles. Like atrial contraction, ventricular contractions result from depolarization, which would involve the inward movement of cations like sodium ions.

What happens during the Q and R wave?

Q and R waves is contraction of the ventricles. Like atrial contraction, ventricular contractions result from depolarization, which would involve the inward movement of cations like sodium ions.

SDS-PAGE

SDS-PAGE is an electrophoretic technique which involves the binding of the anionic detergent SDS to a polypeptide chain. SDS binding denatures and imparts an even distribution of charge per unit mass to the protein, resulting in fractionation by approximate size alone during electrophoresis.

What happens during the T waves?

T and U waves occur due to repolarization, which takes place when positive ions are pumped back out of the cell to return to rest potential prior to the next heartbeat

What is Ohm's Law?

V= IR = resistance * current

What is an imune?

contains a carbon-nitrogen double bond

When comparing the -ous acids and -ic acids, the -ous acids will have one ___ oxygen atoms than their -ic counterparts.

fewer

With high-energy radiation produced by the γ rays, it would produce enough sufficient energy to excite electrons to higher energy levels, eject electrons from molecular orbitals and produce _____.

generate free radicals.

The Longer-wavelength light corresponds to _______-energy light.

lower -loss of vibrational energy with electrons from excited state to ground state

If the initial starch is an entirely linear polysaccharide, then a debranching enzyme like a (high abs, no current) enzyme would have ______ effect on absorbance, and it would remain _______ over time.

no effect on absorbance, Remain constant over time

This means that whether after one (Co) or five (X) half-lives, the atomic mass will be the ______ in both samples.

same. While β-decay does cause a nuclear transmutation of protons to neutrons (β-plus) or neutrons to protons (β-minus), the atomic mass lost in these processes is negligible. (SAME MASSES!)

Affinity chromatography

separate molecules, including proteins, based upon their specific interaction with the stationary phase. During protein purification, this is often an antigen-antibody, receptor-ligand, or enzyme-substrate interaction.

Ion-exchange chromatography

separates charged particles based on their affinity for charged elements of the ion exchange column.

Gibbs Free energy equation?

ΔG = ΔH - TΔS.