Question 1

Which of the following statements best describes isotopes of an element?

Accepted Answer

Isotopes have the same number of protons but different numbers of neutrons.

Question 2

A neutral atom of $^{197}_{79}\mathrm{Au}$ (gold-197) contains how many protons, neutrons, and electrons?

Accepted Answer

79 protons, 118 neutrons, 79 electrons

Question 3

Calculate the atomic weight of an element with two isotopes: 60.0% abundance of isotope A (mass = 10.0 amu) and 40.0% abundance of isotope B (mass = 12.0 amu).

Accepted Answer

$10.8\ \mathrm{amu}$

Question 4

Which of the following elements is NOT a diatomic molecule in its natural state?

Accepted Answer

Carbon

Question 5

What is the empirical formula for hydrogen peroxide ($\mathrm{H_2O_2}$)?

Accepted Answer

$\mathrm{HO}$

Question 6

Which of the following best describes the difference between a molecular formula and an empirical formula?

Accepted Answer

A molecular formula shows the exact number of atoms of each element, while an empirical formula shows the simplest whole-number ratio.

Question 7

Which of the following ions is a cation?

Accepted Answer

$\mathrm{Na^+}$

Question 8

How many electrons are present in a $\mathrm{^{31}_{15}P^{3-}}$ ion?

Accepted Answer

18

Question 9

Which of the following compounds is named correctly?

Accepted Answer

$\mathrm{FeCl_3}$: iron(III) chloride

Question 10

What is the correct formula for magnesium nitride?

Accepted Answer

$\mathrm{Mg_3N_2}$

Question 11

Which of the following is the correct name for $\mathrm{H_2SO_4}$?

Accepted Answer

Sulfuric acid

Question 12

What is the correct name for $\mathrm{K_2SO_4}$?

Accepted Answer

Potassium sulfate

Question 13

Which of the following is a polyatomic ion?

Accepted Answer

$\mathrm{NO_3^-}$

Question 14

What is the correct name for $\mathrm{CuSO_4}$?

Accepted Answer

Copper(II) sulfate

Question 15

Which of the following is the correct formula for dinitrogen tetroxide?

Accepted Answer

$\mathrm{N_2O_4}$

Question 16

Which of the following best explains why ionic compounds are electrically neutral?

Accepted Answer

The total positive charge of the cations equals the total negative charge of the anions.

Question 17

What is the correct name for $\mathrm{HNO_2}$?

Accepted Answer

Nitrous acid

Question 18

Which of the following is the correct formula for ammonium sulfate?

Accepted Answer

$\mathrm{(NH_4)_2SO_4}$

Question 19

A sample of chlorine contains 75.78% $^{35}\mathrm{Cl}$ (mass = 34.969 amu) and 24.22% $^{37}\mathrm{Cl}$ (mass = 36.966 amu). What is the atomic weight of chlorine?

Accepted Answer

$35.45\ \mathrm{amu}$

Question 20

Which of the following is the correct name for $\mathrm{PCl_5}$?

Accepted Answer

Phosphorus pentachloride

Atoms, Molecules, and Ions: Structured Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards