Question 1

According to Dalton’s Atomic Theory, which statement is INCORRECT?

Accepted Answer

Atoms of one element cannot change into atoms of another element.

Question 2

Which subatomic particle is responsible for the chemical properties of an element?

Accepted Answer

Electron

Question 3

A neutral atom of sodium (Na) has an atomic number of 11. How many electrons does it have?

Accepted Answer

$$11$$

Question 4

Which of the following best describes an isotope?

Accepted Answer

Atoms with the same number of protons but different numbers of neutrons.

Question 5

Which equation correctly represents the formation of a fluoride ion?

Accepted Answer

$$\mathrm{F} + e^- \rightarrow \mathrm{F}^-$$

Question 6

Which of the following statements about cations is TRUE?

Accepted Answer

Cations are formed when an atom loses electrons.

Question 7

Given the following data, which subatomic particle has the smallest mass?

Accepted Answer

Electron

Question 8

A neutral atom has 17 protons and 18 neutrons. What is its mass number?

Accepted Answer

$$35$$

Question 9

Which of the following is a correct statement about the charge of a neutron?

Accepted Answer

It has no charge

Question 10

A magnesium ion has a charge of $$2+. $$How many electrons does it have if its atomic number is $$12$$?

Accepted Answer

$$10$$

Question 11

Which of the following best explains why atoms are electrically neutral?

Accepted Answer

They have equal numbers of protons and electrons.

Question 12

Which of the following is a real-world application of ions?

Accepted Answer

Sodium ions ($$\mathrm{Na}^+) $$are essential for nerve impulse transmission in the human body.

Question 13

Which of the following is the correct symbol for an atom with 6 protons, 6 neutrons, and 6 electrons?

Accepted Answer

$$^{12}_{6}\mathrm{C}$$

Question 14

If an atom has 15 protons, 16 neutrons, and 18 electrons, what is its charge?

Accepted Answer

$$3-$$

Question 15

Which of the following best describes the difference between a cation and an anion?

Accepted Answer

A cation has more protons than electrons, while an anion has more electrons than protons.

Question 16

Which of the following is a correct representation of the sodium ion formation?

Accepted Answer

$$\mathrm{Na} \rightarrow \mathrm{Na}^+ + e^-$$

Question 17

Which of the following statements about the mass of subatomic particles is correct?

Accepted Answer

The mass of a neutron is slightly greater than that of a proton.

Question 18

Which of the following is NOT a postulate of Dalton’s Atomic Theory?

Accepted Answer

Atoms are made up of protons, neutrons, and electrons.

Question 19

A chlorine atom has 17 protons and 18 neutrons. What is the isotope symbol for this atom?

Accepted Answer

$$^{35}_{17}\mathrm{Cl}$$

Question 20

Which of the following best explains why isotopes of the same element have different masses?

Accepted Answer

They have different numbers of neutrons.

Introduction to the Atom: Structure, Subatomic Particles, and Ions

Study Guide - Practice Questions