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Suppose that, in a given reaction, the enthalpy (H) increases by 10 units, and the disorder (TS) increases by 12 units. By how many units did the Gibbs free energy change? A.-2 B.-22 C.22 D.2

A.-2

In this figure the solid blue curve plots free energy of a reaction against progress of that reaction. This reaction is: A.endergonic. B.More information is needed in order to answer this question. C.exergonic.

A. endergonic

Many cellular processes represent work that requires the expenditure of energy. Which of the actions is not a cellular process that requires the cell to expend energy? A.Diffusion of water into cells. B.Contraction of muscle cells. C.Synthesis of large biomolecules like proteins and nucleic acids. D.Keeping sodium ion concentration lower inside a cell than outside the cell.

A.Diffusion of water into cells.

Which of the factors accounts for the higher potential energy of C-C and C-H bonds compared to C-O and H-O bonds? A.The C-C and C-H bonds are weak, thus requiring a lot of energy to hold together. B.The C-O and H-O bonds are weak, thus requiring less energy to hold together. C.The C-C and C-H bonds are strong, thus requiring a lot of energy to hold together. D.The C-O and H-O bonds are strong, thus requiring a lot of energy to hold together.

A.The C-C and C-H bonds are weak, thus requiring a lot of energy to hold together.

Which of the choices is an example of potential energy? A.an electrochemical gradient across the cell membrane B.flow of calcium ions through a membrane channel C.contraction of a muscle cell D.chemical transport, as in the sodium-potassium pump

A.an electrochemical gradient across the cell membrane

Which labeled arrow in the figure represents the activation energy (EA)? A.arrow b B.arrow d C.arrow c D.arrow a E.arrow e

A.arrow b

If you added an enzyme that catalyzes the reaction shown, you would predict that ____ would be reduced but ____ would remain the same. A.arrow b; arrow e B.arrow b; arrow c C.arrow e; arrow b D.arrow d; arrow e E.arrow e; arrow c

A.arrow b; arrow e

The first law of thermodynamics states that: A.energy cannot be created or destroyed. B.only eukaryotic cells can produce ATP. C.combustion engines are 100% efficient. D.there is an increase in disorder in the universe over time.

A.energy cannot be created or destroyed.

When chemical reactions occur the _____________ but the _____________. A.pairing of atoms that share electron pairs changes; individual atomic nuclei stay the same B.number of protons and neutrons changes; shared electrons stay the same C.number of shared electron pairs is unchanged; number of atomic nuclei changes

A.pairing of atoms that share electron pairs changes; individual atomic nuclei stay the same

What hypothesis did this experiment test? A.The level of radioactivity can change on either side of a selectively permeable membrane. B.Enzymes form complexes with substrates. C.Substrates form complexes with other substrates. D.Selectively permeable membranes are permeable to some enzymes but not others. E.Enzymes form complexes with other enzymes.

B.Enzymes form complexes with substrates. Arrhenius's hypothesis was that enzymes form complexes with substrates during chemical reactions. Based on Stern's previous results on the enzyme catalase, this experiment tests whether another enzyme (beta-galactosidase) also forms complexes with its substrate.

Which of the statements is true about exergonic reactions? A.Exergonic reactions have a positive ΔG. B.Exergonic reactions are catabolic. C.Exergonic reactions measure the strength of an ionic bond. D.Exergonic reactions are found only in biological systems. E.Exergonic reactions consume energy.

B.Exergonic reactions are catabolic.

Which of the choices is an example of kinetic energy? A.a C-H bond in a sugar molecule B.a photon of light C.gasoline in an auto gas tank D.a ball at the top of stairs E.water behind a dam

B.a photon of light

Which labeled arrow in the figure represents the change in free energy of the reaction (DG)? A.arrow b B.arrow e C.arrow d D.arrow a E.arrow c

B.arrow e

The transition state is that portion of the progress of a chemical reaction with a large amount of energy found in _______ reactions. A.endergonicboth B.endergonic and exergonic C.exergonic D.non-spontaneous

B.endergonic and exergonic

The carbon atom in CO2 shares _______ electron pairs. After the reaction with H2O to form H2CO3 is completed the carbon atom shares ________ electron pairs. A.two; three B.four; four C.three; two D.two; two

B.four; four

Before this experiment was performed, Kurt Stern had already shown that the enzyme catalase forms a complex with its substrate. Therefore, this current set of experiments: A.repeated the exact same experiment again. B.investigated a different enzyme and substrate. C.served as a negative control for Stern's experiment. D.was not necessary to support the hypothesis that enzymes form complexes with substrates in general. E.served as a positive control for Stern's experiment.

B.investigated a different enzyme and substrate.

Carbon-carbon covalent bonds, such as the ones in carbohydrates and lipids, are _____ and have _____. A.strong; a lot of kinetic energy B.weak; a lot of potential energy C.strong; little kinetic energy D.weak; little potential energy E.strong; a lot of potential energy

B.weak; a lot of potential energy

When H2CO3 reacts to form CO2 and H2O, what is the net change in the number of shared electron pairs? A.-3 B. +2 C. 0 D. -2

C. 0

When chemical reactions occur the _____ but the _____. A.identity of atoms changes; arrangement of bonds is retained B.number of bonds per atom changes; total number of bonds is retained C.atoms retain their identities; arrangement of bonds changes

C.atoms retain their identities; arrangement of bonds changes

Oak trees are categorized as: A.chemoheterotrophs. B.photoheterotrophs. C.photoautotrophs. D.chemoautotrophs.

C.photoautotrophs. Oak trees are plants. They photosynthesize to capture sunlight energy while building organic molecules starting from inorganic carbon dioxide.

Oak trees are categorized as: A.chemoheterotrophs. B.photoheterotrophs. C.photoautotrophs. Oak trees are plants. They photosynthesize to capture sunlight energy while building organic molecules starting from inorganic carbon dioxide. D.chemoautotrophs.

C.photoautotrophs. Oak trees are plants. They photosynthesize to capture sunlight energy while building organic molecules starting from inorganic carbon dioxide.

As a cat pounces on a mouse, its muscles consume 10 units of potential energy (which the cat previously gained from the food it consumed). However, the pounce itself only required 4 units of kinetic energy. How many units of energy were dissipated as heat? A.2.5 B.14 C.10 D.6 E.4

D.6

In a reaction, enzymes change the: A.first law of thermodynamics. B.second law of thermodynamics. C.ΔG.types of products. D.activation energy.

D.activation energy.

Enzymes in your gastrointestinal tract digest your lunch. These chemical reactions are categorized as: A.anabolism. B.chemiosmosis. C.diffusion. D.catabolism. E.active transport.

D.catabolism.

Of the molecules, which has the greatest chemical potential energy? A.water B.alanine C.carbon dioxide D.glucose E.sodium chloride

D.glucose

In a related experiment, Kurt Stern studied catalase, which is an enzyme that catalyzes the reaction:2H2O2→2H2O+O2Hydrogen peroxide Water OxygenIn this experiment, we would expect a complex to be formed between: A.water and oxygen. B.catalase and water. C.catalase and oxygen. D.hydrogen peroxide and water. E.catalase and hydrogen peroxide.

E.catalase and hydrogen peroxide. The substrate in this reaction is 2H2O2 (hydrogen peroxide), and the enzyme is catalase. Therefore, the complex includes hydrogen peroxide and catalase.