Question 1

Which of the following best describes a compound?

Accepted Answer

A substance composed of two or more elements chemically combined in a definite ratio.

Question 2

Brass is an example of which type of matter?

Accepted Answer

Homogeneous mixture

Question 3

Which of the following is a physical property of copper?

Accepted Answer

Copper is a shiny, reddish-orange metal.

Question 4

A mixture of sand and salt water can be separated by which method?

Accepted Answer

Filtration

Question 5

Which of the following is NOT a pure substance?

Accepted Answer

Air

Question 6

Which statement about elements is correct?

Accepted Answer

Elements contain only one type of atom.

Question 7

A sample of water is classified as:

Accepted Answer

A compound

Question 8

Which of the following is a heterogeneous mixture?

Accepted Answer

Water and copper metal

Question 9

Which process is used to separate the elements sodium and chlorine from table salt (NaCl)?

Accepted Answer

Chemical decomposition

Question 10

Which of the following is true about homogeneous mixtures?

Accepted Answer

They have a uniform composition throughout.

Question 11

Which of the following is an example of a physical change?

Accepted Answer

Melting ice on the street

Question 12

What is the density of a substance if its mass is $27.2\ \mathrm{g}$ and its volume is $2.00\ \mathrm{mL}$?

Accepted Answer

$13.6\ \mathrm{g/mL}$

Question 13

Specific gravity is defined as:

Accepted Answer

Density of a substance divided by density of water

Question 14

Which of the following is a chemical property?

Accepted Answer

Ability to react with oxygen

Question 15

Which of the following statements about compounds is correct?

Accepted Answer

Compounds have a fixed ratio of elements.

Question 16

Which of the following is a correct example of a homogeneous mixture?

Accepted Answer

Steel

Question 17

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

Accepted Answer

Can be separated by physical means

Question 18

Which of the following is an element?

Accepted Answer

Copper

Question 19

Which of the following is true about mixtures?

Accepted Answer

Mixtures can be separated by physical methods.

Question 20

Which of the following is a correct statement about the decomposition of table salt (NaCl)?

Accepted Answer

It produces the elements sodium and chlorine.

Classification of Matter and Density Concepts in GOB Chemistry

Study Guide - Practice Questions