Question 1

Which of the following best describes a substitution reaction in organic chemistry?

Accepted Answer

A reaction where one atom or group of atoms is replaced by another.

Question 2

In homolytic cleavage of a covalent bond, what is the result?

Accepted Answer

Formation of two radicals, each with an unpaired electron.

Question 3

Which statement correctly defines a Brønsted–Lowry acid?

Accepted Answer

A substance that can donate a proton.

Question 4

According to the Lewis definition, which of the following is a Lewis base?

Accepted Answer

A species that donates an electron pair.

Question 5

Carbocations are considered:

Accepted Answer

Lewis acids and electrophiles.

Question 6

Which of the following best describes the use of curved arrows in reaction mechanisms?

Accepted Answer

They indicate the direction of electron flow from the source to the receiver.

Question 7

Given the equilibrium constant for acetic acid ionization: $$K_{eq} = \frac{[CH_3CO_2^-][H_3O^+]}{[CH_3CO_2H][H_2O]}$$, what is the expression for the acidity constant $$K_a$$?

Accepted Answer

$$K_a = \frac{[CH_3CO_2^-][H_3O^+]}{[CH_3CO_2H]}$$

Question 8

Which acid is stronger based on its pKa value?

Accepted Answer

Acid with pKa = 0

Question 9

What is the relationship between acid strength and conjugate base strength?

Accepted Answer

The stronger the acid, the weaker its conjugate base.

Question 10

Which factor increases acidity as you descend a vertical column in the periodic table?

Accepted Answer

Decreasing bond strength.

Question 11

How does hybridization affect the acidity of hydrocarbons?

Accepted Answer

More s character increases acidity.

Question 12

Which effect stabilizes the conjugate base of acetic acid more than that of ethanol?

Accepted Answer

Both inductive and resonance effects.

Question 13

Which of the following is a real-world example of an addition reaction?

Accepted Answer

Ethylene reacting with Br$$_2 to $$form 1,2-dibromoethane.

Question 14

What is the correct formula for calculating pKa?

Accepted Answer

$$pK_a = -\log K_a$$

Question 15

Which statement about acid–base reactions is correct?

Accepted Answer

They always favor the formation of the weaker acid and base.

Question 16

Which of the following is a nucleophile?

Accepted Answer

A species that seeks a positive center, such as a carbocation.

Question 17

Which equation relates the standard free energy change to the equilibrium constant?

Accepted Answer

$$\Delta G^\circ = -RT \ln K_{eq}$$

Question 18

Which of the following statements about solvation and acidity is correct?

Accepted Answer

Acids are weaker in the gas phase than in solution due to solvation.

Question 19

Which of the following is true about inductive effects?

Accepted Answer

Inductive effects are electronic effects transmitted through bonds and weaken with distance.

Question 20

Which factor contributes to the greater acidity of trifluoroethanol compared to ethanol?

Accepted Answer

The presence of electron-withdrawing fluorine atoms stabilizing the conjugate base.

Chapter 3: Acids, Bases, and Reaction Mechanisms in Organic Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard