Question 1

Which of the following statements best explains why the ionization energy of oxygen is higher than that of sulfur?

Accepted Answer

Oxygen has a higher electronegativity, resulting in a stronger attraction between the nucleus and valence electrons.

Question 2

Which molecule below has a nonpolar covalent bond?

Accepted Answer

O$$_2$$

Question 3

Given the following Lewis structure for CO$$_2$$, what is the formal charge on the oxygen atom?

$$\mathrm{O=C=O}$$

Accepted Answer

$$0$$

Question 4

Which of the following is an exception to the octet rule?

Accepted Answer

BF$$_3$$

Question 5

Which of the following best describes a resonance structure?

Accepted Answer

A structure where electrons are delocalized and can be represented by multiple valid Lewis structures.

Question 6

Which of the following molecules is amphiprotic?

Accepted Answer

H$$_2O$$

Question 7

Which of the following is a Bronsted-Lowry base?

Accepted Answer

NH$$_3$$

Question 8

What is the hybridization of the central carbon atom in ethene (C$$_2H$_4$$)?

Accepted Answer

$$sp^2$$

Question 9

Which of the following best describes a nucleophile?

Accepted Answer

A species that donates electrons to form a new bond.

Question 10

Which of the following molecules will have the highest boiling point?

Accepted Answer

H$$_2O$$

Question 11

What is the IUPAC name for the following structure?

$$\mathrm{CH_3CH_2CH_2CH_3}$$

Accepted Answer

Butane

Question 12

Which of the following is a constitutional isomer of butane?

Accepted Answer

Isobutane ($$\mathrm{CH_3CH(CH_3$)_2})$$

Question 13

Which of the following best describes the difference between a sigma ($$\sigma) $$bond and a pi ($$\pi) $$bond?

Accepted Answer

A $$\sigma$$ bond is stronger and formed by end-to-end overlap, while a $$\pi$$ bond is weaker and formed by side-to-side overlap.

Question 14

Which of the following is the correct balanced equation for the combustion of propane ($$\mathrm{C_3H_8}$$)?

Accepted Answer

$$\mathrm{C_3H_8 + 5O_2 \rightarrow 3CO_2 + 4H_2O}$$

Question 15

Which of the following molecules contains a chiral center?

Accepted Answer

2-butanol ($$\mathrm{CH_3CH(OH)CH_2CH_3})$$

Question 16

Which of the following statements about enantiomers is correct?

Accepted Answer

Enantiomers have identical physical properties except for their interaction with plane-polarized light.

Question 17

Which of the following is the correct formula for an alkane with 7 carbon atoms?

Accepted Answer

$$\mathrm{C_7H_{16}}$$

Question 18

Which of the following statements best explains why water is more soluble in ethanol than in hexane?

Accepted Answer

Ethanol can form hydrogen bonds with water, while hexane cannot.

Question 19

Which of the following is the correct relationship between pKa and acid strength?

Accepted Answer

A lower pKa value indicates a stronger acid.

Question 20

A mixture contains 70% of the R enantiomer and 30% of the S enantiomer. What is the enantiomeric excess (ee)?

Accepted Answer

$$40\%$$

Organic Chemistry Unit 1: Key Concepts, Vocabulary, and Skills Study Guide

Study Guide - Practice Questions