Question 1

Which of the following best describes a molecule of $$\mathrm{H_2SO_4}$$?

Accepted Answer

A pure substance composed of a fixed ratio of hydrogen, sulfur, and oxygen atoms.

Question 2

How many atoms are present in 2 molecules of $$\mathrm{H_2SO_4}$$?

Accepted Answer

28 atoms

Question 3

Which statement correctly distinguishes a pure substance from a mixture?

Accepted Answer

A pure substance has a fixed composition and constant properties.

Question 4

Given the formula $$\mathrm{Ca_3$(PO_4$)_2}$$, how many oxygen atoms are present in 3 molecules?

Accepted Answer

24 atoms

Question 5

Which of the following is an example of a simple pure substance?

Accepted Answer

Oxygen gas ($$\mathrm{O_2$})$$

Question 6

What is the atomicity of glucose ($$\mathrm{C_6H_{12}O_6$}$$)?

Accepted Answer

24 atoms

Question 7

Which property is NOT characteristic of a mixture?

Accepted Answer

Constant boiling point

Question 8

If you have 5 molecules of $$\mathrm{$$CaSO_4$$ \cdot 5H_2O}$$, how many hydrogen atoms are present?

Accepted Answer

50 atoms

Question 9

Which of the following best describes metallic bonding?

Accepted Answer

Electrons are delocalized and move freely among metal atoms.

Question 10

Which scenario represents a eutectic mixture?

Accepted Answer

A mixture of two metals with a melting point lower than either pure metal.

Question 11

How many atoms are present in 3 molecules of $$\mathrm{H_2SO_4}$$?

Accepted Answer

24 atoms

Question 12

Which of the following is NOT a characteristic of a pure substance?

Accepted Answer

Can be separated by physical means

Question 13

What is the total number of atoms in one molecule of $$\mathrm{Ca_3$(PO_4$)_2}$$?

Accepted Answer

19 atoms

Question 14

Which of the following is an example of a mixture?

Accepted Answer

Air

Question 15

Which statement about atomicity is correct?

Accepted Answer

Atomicity is the number of atoms in a molecule.

Question 16

Which of the following substances has a constant melting point?

Accepted Answer

Pure sodium chloride ($$\mathrm{NaCl})$$

Question 17

What is the correct definition of a pure substance?

Accepted Answer

A material with fixed composition and constant properties.

Question 18

Which of the following is a characteristic of a mixture?

Accepted Answer

Variable composition

Question 19

How many phosphorus atoms are present in 3 molecules of $$\mathrm{Ca_3$(PO_4$)_2}$$?

Accepted Answer

6 atoms

Question 20

Which of the following is NOT a simple substance?

Accepted Answer

Water ($$\mathrm{H_2O})$$

Atoms, Molecules, and Classification of Substances

Study Guide - Practice Questions