Question 1

Which of the following electron configurations correctly represents the ground state of phosphorus (Z = 15)?

Accepted Answer

$$1s^2$$ $$2s^2$$ $$2p^6$$ $$3s^2$$ $$3p^3$$

Question 2

According to the periodic trend, which element is the most electronegative in Group 7A?

Accepted Answer

F

Question 3

Which of the following statements about the octet rule is correct for the oxygen atom in the molecule shown (methanol, CH3OH)?

Accepted Answer

Oxygen possesses 8 octet electrons: 6 valence and 2 shared electrons.

Question 4

What is the formal charge on the central carbon atom in the thiocyanate ion, SCN⁻, given the following Lewis structure: N≡C–S⁻?

Accepted Answer

0

Question 5

Which of the following is the correct condensed electron configuration for chlorine (Z = 17)?

Accepted Answer

[Ne] $$3s^2$$ $$3p^5$$

Question 6

Which of the following molecules is nonpolar?

Accepted Answer

CO2

Question 7

How many resonance structures can be drawn for the nitrate ion, NO3⁻?

Accepted Answer

3

Question 8

What is the hybridization of the central atom in HCN?

Accepted Answer

sp

Question 9

Which of the following best describes a resonance hybrid?

Accepted Answer

A composite of all major resonance structures

Question 10

Which of the following functional groups is present in acetone?

Accepted Answer

Ketone

Question 11

Which of the following statements about the Aufbau Principle is correct?

Accepted Answer

Electrons fill the lowest energy orbitals first

Question 12

Which of the following molecules is both organic and a hydrocarbon?

Accepted Answer

C6H6 (benzene)

Question 13

A molecule has three electron groups and no lone pairs on the central atom. What is its electron geometry and hybridization?

Accepted Answer

Trigonal planar, sp2

Question 14

Which of the following best explains why CO2 is nonpolar, even though it contains polar bonds?

Accepted Answer

The molecule is linear and the bond dipoles cancel each other out

Question 15

What is the formal charge on the oxygen atom in the hydronium ion, H3O+?

Accepted Answer

0

Question 16

Which of the following statements about electronegativity is correct?

Accepted Answer

Electronegativity increases from left to right across a period and increases going up a group

Question 17

Which of the following is the correct formula for calculating the formal charge of an atom in a molecule?

Accepted Answer

Formal Charge = Valence Electrons - (Nonbonding Electrons + 1/2 Bonding Electrons)

Question 18

Which of the following best describes a molecule that is polar?

Accepted Answer

A molecule with an asymmetric distribution of charge due to differences in electronegativity and molecular geometry

Question 19

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 20

Which of the following best describes the hybridization and number of unhybridized p orbitals on the central atom in ethene (C2H4)?

Accepted Answer

sp2 hybridization, 1 unhybridized p orbital

General Chemistry: Atomic Structure, Bonding, and Molecular Properties Study Guide

Study Guide - Practice Questions