Question 1

Which of the following best describes a chemical change?

Accepted Answer

Burning wood to produce ash and gases

Question 2

Which statement correctly distinguishes between elements and compounds?

Accepted Answer

Elements consist of only one kind of atom, while compounds consist of two or more different elements bonded together.

Question 3

A student mixes sand and iron filings. Which type of matter is formed, and how can it be separated?

Accepted Answer

A mixture; by physical separation such as using a magnet

Question 4

Which property is intensive and does NOT depend on the amount of substance present?

Accepted Answer

Density

Question 5

Which of the following is a pure substance?

Accepted Answer

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

Question 6

A sample of water is heated until it boils. Which type of change is occurring?

Accepted Answer

Physical change, because the composition remains the same

Question 7

Which of the following best explains why compounds have fixed composition?

Accepted Answer

Compounds are made of two or more elements bonded in definite proportions.

Question 8

Which of the following is an example of a chemical property?

Accepted Answer

Ability to react with oxygen

Question 9

A mixture of ethanol and water is separated by distillation. What property allows this separation?

Accepted Answer

Difference in boiling points

Question 10

Which of the following statements about mixtures is correct?

Accepted Answer

Mixtures can be separated into their components by physical means.

Question 11

Which property is considered extensive?

Accepted Answer

Mass

Question 12

Which of the following best describes the atom?

Accepted Answer

The basic unit of matter

Question 13

Which process is a chemical change?

Accepted Answer

Rusting of iron ($$\mathrm{Fe}$$ reacting with $$\mathrm{O_2$})$$

Question 14

A student claims that density changes when the amount of substance changes. Which concept refutes this claim?

Accepted Answer

Density is an intensive property.

Question 15

Which of the following is NOT a physical property?

Accepted Answer

Ability to burn in air

Question 16

Which of the following is a mixture?

Accepted Answer

Air

Question 17

Which statement about physical changes is correct?

Accepted Answer

Physical changes do not alter the chemical composition.

Question 18

A sample of copper is hammered into a thin sheet. What type of change is this?

Accepted Answer

Physical change

Question 19

Which of the following best explains why water ($$\mathrm{H_2O}) is a $$compound?

Accepted Answer

It can be separated into hydrogen and oxygen by chemical means.

Question 20

Which of the following is an example of an extensive property?

Accepted Answer

Volume

Fundamental Concepts in General Chemistry: Matter, Substances, and Properties

Study Guide - Practice Questions