Question 1

Which of the following statements best explains why trans-2-butene is more stable than cis-2-butene?

Accepted Answer

Trans-2-butene has substituents farther apart, reducing steric strain and increasing stability.

Question 2

Which formula represents the general formula for alkenes?

Accepted Answer

$\mathrm{C}_n\mathrm{H}_{2n}$

Question 3

A reaction has a negative $\Delta G^{\circ}$. What does this indicate about the reaction?

Accepted Answer

The reaction is exergonic and thermodynamically favorable.

Question 4

Which of the following best describes the role of a catalyst in a chemical reaction?

Accepted Answer

A catalyst provides a new pathway with a lower activation energy.

Question 5

Which statement about the heat of hydrogenation ($\Delta H^{\circ}$) of alkenes is correct?

Accepted Answer

A less negative $\Delta H^{\circ}$ indicates a more stable alkene.

Question 6

Which factor does NOT increase the rate of a chemical reaction according to collision theory?

Accepted Answer

Increasing the activation energy.

Question 7

In the reaction coordinate diagram, what does the highest point represent?

Accepted Answer

The transition state.

Question 8

Which of the following is true about the stability of alkenes?

Accepted Answer

Alkenes with more alkyl substituents on the double bond are more stable.

Question 9

Which of the following best describes an electrophile?

Accepted Answer

An atom or molecule with a positive or partial positive charge seeking electrons.

Question 10

What is the effect of increasing temperature on the rate of a chemical reaction?

Accepted Answer

It increases the frequency of collisions and the rate of reaction.

Question 11

Which of the following is the smallest possible group containing an allylic carbon?

Accepted Answer

Allyl group

Question 12

Which of the following statements about hydrogenation of alkenes is correct?

Accepted Answer

Hydrogenation requires a catalyst and is exothermic.

Question 13

A compound releases more heat during hydrogenation. What does this indicate about its stability?

Accepted Answer

It is less stable.

Question 14

Which of the following is true about the mechanism of a reaction?

Accepted Answer

It describes how reactants are changed into products.

Question 15

What is the correct expression for Gibbs free energy change ($\Delta G^{\circ}$)?

Accepted Answer

$\Delta G^{\circ} = 	ext{free energy of products} - 	ext{free energy of reactants}$

Question 16

Which of the following best describes a nucleophile?

Accepted Answer

An electron-rich atom or molecule seeking a nucleus.

Question 17

Which of the following is true about the transition state in a reaction coordinate diagram?

Accepted Answer

It is the highest energy point and determines the activation energy.

Question 18

Which of the following is a correct statement about coupled reactions?

Accepted Answer

An exergonic reaction drives the endergonic reaction that follows.

Question 19

Which of the following is true about enzymes in catalysis?

Accepted Answer

Enzymes are proteins that speed up reactions by lowering activation energy.

Question 20

Which of the following best describes molecular recognition?

Accepted Answer

The ability of a molecule to recognize another molecule as a result of their interaction.

Chapter 5: Alkenes – Structure, Reactivity, and Thermodynamics

Study Guide - Practice Questions