Question 1

Which of the following molecules is polar?

Accepted Answer

Water ($$H_2O)$$

Question 2

Given the molecule $$CH_3COOH ($$acetic acid), what is the formal charge on the oxygen atom in the hydroxyl group?

Accepted Answer

$$0$$

Question 3

Which atomic orbital is involved in the formation of the bond between the carbon and chlorine in $$CH_3Cl$$?

Accepted Answer

$$sp^3$$

Question 4

In the acid-base equilibrium between acetic acid and water, which species acts as the conjugate base?

Accepted Answer

$$CH_3COO^-$$

Question 5

What is the $$pK_a$$ range for a typical carboxylic acid such as acetic acid?

Accepted Answer

$$4-5$$

Question 6

Which of the following best describes the hybridization of the central carbon in formaldehyde ($$CH_2O$$)?

Accepted Answer

$$sp^2$$

Question 7

If a molecule has a lone pair on a nitrogen atom, which orbital does the lone pair occupy?

Accepted Answer

$$sp^3$$

Question 8

Which of the following is the correct arrow-pushing mechanism for the deprotonation of acetic acid by hydroxide ion?

Accepted Answer

Arrow from $$OH^-$$ lone pair to the acidic hydrogen, arrow from O-H bond to the oxygen atom of acetic acid

Question 9

Which of the following statements about formal charges is correct?

Accepted Answer

Formal charge is calculated by subtracting the sum of bonds and lone pairs from the number of valence electrons

Question 10

Which of the following molecules has a net dipole moment?

Accepted Answer

Ammonia ($$NH_3)$$

Question 11

In the reaction between acetic acid and sodium hydroxide, what is the major organic product?

Accepted Answer

Acetate ion ($$CH_3COO^-)$$

Question 12

Which of the following is the correct Lewis structure for the acetate ion ($$CH_3COO^-$$)?

Accepted Answer

One oxygen has a double bond to carbon, the other has a single bond and three lone pairs

Question 13

Which of the following best explains why acetic acid is more acidic than ethanol?

Accepted Answer

The carboxylate ion is stabilized by resonance

Question 14

What is the hybridization of the oxygen atom in water ($$H_2O$$)?

Accepted Answer

$$sp^3$$

Question 15

Which of the following is the correct order of acid strength (from strongest to weakest) for the following: $$HCl$$, $$CH_3COOH$$, $$CH_3CH_2OH$$?

Accepted Answer

$$HCl \u003e CH_3COOH \u003e CH_3CH_2OH$$

Question 16

Which of the following is a correct statement about resonance structures?

Accepted Answer

Resonance structures differ only in the placement of electrons, not atoms

Question 17

In a reaction mechanism, what does a curved arrow represent?

Accepted Answer

Movement of electron pairs

Question 18

Which of the following is the conjugate acid of ammonia ($$NH_3$$)?

Accepted Answer

$$NH_4$$^+$$

Question 19

Which of the following molecules contains an atom with a formal charge of $$-1$$?

Accepted Answer

Hydroxide ion ($$OH^-)$$

Question 20

Which of the following is the correct $$pK_a$$ value for the conjugate acid of water ($$H_3O^+$$)?

Accepted Answer

$$-1.7$$

Organic Chemistry: Exam Questions on Structure, Bonding, and Acid-Base Equilibria

Study Guide - Practice Questions