Question 1

Which of the following statements best describes an exergonic reaction?

Accepted Answer

It gives off energy and has a negative $\Delta G$.

Question 2

A chemical reaction has $\Delta G = +45\ \mathrm{kJ/mol}$. Which statement is true about this reaction?

Accepted Answer

It is endergonic and requires energy input to proceed.

Question 3

Which equation correctly relates Gibbs free energy to enthalpy and entropy?

Accepted Answer

$\Delta G = \Delta H - T\Delta S$

Question 4

Why do enzymes increase the rate of biochemical reactions?

Accepted Answer

They lower the activation energy required for the reaction.

Question 5

Which of the following is true about spontaneous processes?

Accepted Answer

They occur naturally and do not require energy input once started.

Question 6

A reaction is catalyzed by an enzyme. Which of the following statements is correct?

Accepted Answer

The enzyme lowers the activation energy but does not change $\Delta G$.

Question 7

Which food molecule provides the highest energy per gram when metabolized in the body?

Accepted Answer

Fat

Question 8

Which of the following best describes the role of ATP in living systems?

Accepted Answer

ATP transfers energy from exergonic to endergonic reactions.

Question 9

Which factor does NOT increase the rate of a chemical reaction?

Accepted Answer

Decreasing the concentration of reactants

Question 10

Which of the following is a decomposition reaction?

Accepted Answer

$\mathrm{MgClO}_3(s) \rightarrow \mathrm{MgCl}_2(s) + 3\mathrm{O}_2(g)$

Question 11

Which statement about reversible reactions at equilibrium is correct?

Accepted Answer

The rates of the forward and reverse reactions are equal.

Question 12

Combustion of glucose in the body is an example of which type of reaction?

Accepted Answer

Decomposition

Question 13

Which of the following is true about catalysts?

Accepted Answer

They lower the activation energy and can be reused.

Question 14

A reaction has a high activation energy. What is the most likely effect on the reaction rate?

Accepted Answer

The reaction rate will be slow.

Question 15

Which of the following is an example of an exchange (double displacement) reaction?

Accepted Answer

$\mathrm{AB} + \mathrm{CD} \rightarrow \mathrm{AD} + \mathrm{CB}$

Question 16

Which of the following best explains why fats are used as energy storage molecules in the body?

Accepted Answer

Fats provide more energy per gram than carbohydrates or proteins.

Question 17

Which of the following is NOT a property of enzymes?

Accepted Answer

They are consumed during the reaction.

Question 18

Which of the following reactions is considered irreversible in biological systems?

Accepted Answer

Combustion of glucose to carbon dioxide and water

Question 19

Which of the following best describes the effect of increasing reactant concentration on reaction rate?

Accepted Answer

It increases the rate by increasing the frequency of collisions.

Question 20

A patient lacks the enzyme lactase. What is the most likely consequence?

Accepted Answer

Symptoms such as diarrhea, bloating, and abdominal cramping after consuming dairy

Chapter 5: Thermodynamics & Kinetics – Chemical Reactions and Energy in GOB Chemistry

Study Guide - Practice Questions