bio chapter 8

Depicts an isolated system

Product

A

Scenario A

Product

B

Reactant

7 units of energy

8 units of energy

15 units of energy

Reactant

Scenario B

Product

B

Product

A

7 units of energy

10 units of energy

15 units of energy

2. Explain why the scenario you chose follows the first law of thermodynamics. Why does the other scenario not follow this first law? (2pts)

3. Of the penguins labeled in this picture, Penguin ______ has the greatest potential energy. (2pts)

A

B

C

4. For the following scenarios, label them as chemical, thermal, kinetic, or potential energy. (7pts)

a. The bonds of sucrose contain __________________ energy.

b. _________________ energy is transferred to my palm when I touch a hot stovetop.

c. When I sit in a sled at the top of a hill, the sled and I contain a lot of ______________ energy.

d. Adenosine triphosphate (ATP) is the ______________ energy harvested during cellular respiration.

e. A bullet contains a devastating amount of ________________ energy.

f. I cannot warm my hands with an ice cube; an ice cube has little ______________ energy.

g. A pulled-back slingshot has a lot of ____________________ energy.

6. For the following prompts, label them as either a catabolic pathway or an anabolic pathway. (14pts)

a. Enzymes breaking a reactant into two products.

b. A + B C

c. Synthesis reaction

d. Requires an input of energy to form new bonds.

e. C B + A

f. Decomposition reaction

g. Cellular respiration

h. Energy is released when bonds are broken.

i. “Downhill” reaction.

j. Photosynthesis

k. Enzymes forcing two reactants together to form a single product.

l. “Uphill” reaction.

m. Hydrolysis

n. Dehydration synthesis

6. Which picture depicts an increase in entropy? Circle your answer. (2pts)

Picture B

Picture A

Picture D

Picture C

7. Which phase of water has the highest amount of entropy? Which phase has the lowest amount of entropy? (2pts)

8. Complete the following chart. (5pts)

9. Below is the formula for calculating ∆G. Label all variables. The units have been provided for you. (2pts)

∆G = ∆H - T∆S

(J/K*mol))

(kJ/mol)

(kJ/mol)

10. What does the “∆” sign mean? (1pt)

11. A reaction at 25.0 o C has a ∆H = 65.5 kJ/mol and ∆S = 127 J/K*mol. (Don’t forget to make sure that your units are correct!) Calculate the value of ∆G and label the reaction as spontaneous/nonspontaneous and exergonic/endergonic. (4pts)

12. ATP is the molecule commonly known to provide energy to the cell; it is a high energy molecule and is therefore very unstable. Study its diagram below. Which part of this molecule is the most unstable? Circle it and explain why. (2pts)

13. How is activation energy used in chemical reactions? (2pts)

14. The “activation energy barrier” is what slows down many reactions, even spontaneous ones. Explain how. (2pts)

15. What are two ways that enzymes can speed up a chemical reaction once its substrate binds to it? (2pts)

16. Complete the following chart about the effects of local activity on enzymes. (4pts)