$$\text{Mass number} = \text{Number of protons} + \text{Number of neutrons}$$

Question 1

Which of the following best describes the difference in electron behavior between ionic and covalent bonds?

Accepted Answer

In ionic bonds, electrons are transferred from one atom to another; in covalent bonds, electrons are shared between atoms.

Question 2

An element has 11 protons and 12 neutrons. What is its atomic number?

Accepted Answer

$$11$$

Question 3

An element has 11 protons and 12 neutrons. What is its mass number?

Accepted Answer

$$23$$

Question 4

Why do noble gases (Group 18) rarely form chemical bonds with other elements?

Accepted Answer

They have a full valence shell, making them chemically stable.

Question 5

Balance the following chemical equation: $$H_2$$ + $$O_2$$ \rightarrow H_2O$$

Accepted Answer

$$2H_2 + O_2$ \rightarrow 2H_2O$$

Question 6

A student tests a mystery liquid with a pH strip that turns bright red, indicating a pH of 2. Which statement is correct?

Accepted Answer

The substance is a strong acid.

Question 7

Which of the following is a real-world example of an ionic compound?

Accepted Answer

Sodium chloride ($$NaCl)$$

Question 8

Which of the following best explains why table salt ($$NaCl) $$dissolves easily in water?

Accepted Answer

The ionic bonds in $$NaCl$$ are broken by the polar water molecules.

Question 9

Which of the following statements about acids and bases is correct?

Accepted Answer

A solution with pH 7 is neutral.

Question 10

A patient is given a solution with a pH of 9 to neutralize stomach acid. What type of substance is this solution?

Accepted Answer

A weak base

Question 11

Which of the following best describes the octet rule as it applies to chemical bonding?

Accepted Answer

Atoms tend to gain, lose, or share electrons to achieve eight electrons in their outer shell.

Question 12

Which of the following is the correct formula for calculating the mass number of an atom?

Accepted Answer

$$	ext{Mass number} = 	ext{Number of protons} + 	ext{Number of neutrons}$$

Question 13

Which of the following best explains why $$O_2 is a $$molecule but not a compound?

Accepted Answer

$$O_2$$ contains only one type of element.

Question 14

Which of the following is a balanced chemical equation for the combustion of hydrogen gas in oxygen to form water?

Accepted Answer

$$2H_2 + O_2$ \rightarrow 2H_2O$$

Question 15

A solution has a pH of 7. Which of the following best describes this solution?

Accepted Answer

It is neutral.

Question 16

Which of the following best describes what happens to the electrons in a covalent bond?

Accepted Answer

Electrons are shared between two atoms.

Question 17

Which of the following is a property of noble gases that explains their lack of chemical reactivity?

Accepted Answer

They have a full outer electron shell.

Question 18

A student mixes hydrochloric acid ($$HCl) $$with sodium hydroxide ($$NaOH) in a $$beaker. Which type of reaction occurs?

Accepted Answer

Neutralization

Question 19

Which of the following best describes the relationship between atomic number and the identity of an element?

Accepted Answer

The atomic number is equal to the number of protons.

Atomic Structure & Bonding: Step-by-Step Chemistry Guidance

Study Guide - Practice Questions