wayground logo

Free Printable Worksheets

NEW

Font size

S
M
L
XL
Worksheets

Grade 8 Elements, Compounds, and Mixtures

Total questions: 24

Worksheet time: 11mins

Name
Class
Date
1.

What is the smallest unit of an element?

a)

ion

b)

compound

c)

molecule

d)

atom

2.

Which of the following is a compound? (A) O2 (B) H2O (C) Na (D) Cl2

a)

NaCl

b)

H2O

c)

CO2

d)

H2

3.

Which of the following is a characteristic of a compound? (A) Fixed composition (B) Variable composition (C) Can be separated by physical means (D) None of the above

a)

A

b)

Can be formed by mixing elements

c)

Has a variable boiling point

d)

Always exists in solid state

4.

Fill in the blank: Elements are made up of only one type of __________.

a)

atom

b)

compound

c)

molecule

d)

mixture

5.

What is the main difference between a compound and a mixture?

a)

A mixture has a fixed composition and chemical bonds, while a compound has variable composition and no chemical bonds.

b)

A compound has a fixed composition and chemical bonds, while a mixture has variable composition and no chemical bonds.

c)

A compound is always a solid, while a mixture can be a liquid or gas.

d)

A compound can be separated by physical means, while a mixture cannot.

6.

Which of the following is a homogeneous mixture? (A) Salad (B) Air (C) Sand and salt (D) Oil and water

a)

Fruit salad

b)

Granite

c)

Vinegar and oil

d)

Air

7.

Drag and drop the following elements into the correct group: Oxygen, Hydrogen, Carbon, Sodium.

a)

Chlorine

b)

Calcium

c)

Nonmetals: [Oxygen, Hydrogen, Carbon]; Metal: [Sodium]

d)

Potassium

8.

Fill in the blank: A __________ is a combination of two or more substances that retain their individual properties.

a)

compound

b)

element

c)

solution

d)

mixture

9.

Which of the following is NOT a property of mixtures? (A) They can be separated by physical means (B) They have a fixed composition (C) They can be homogeneous or heterogeneous (D) They consist of two or more substances

a)

They can only be separated by chemical means

b)

They have a variable composition

c)

They always consist of a single substance

d)

B

10.

What type of mixture is formed when salt is dissolved in water?

a)

solution

b)

colloid

c)

emulsion

d)

suspension

11.

Fill in the blank: The chemical formula for table salt is __________.

a)

NaCl

b)

CaCl2

c)

KCl

d)

MgCl2

12.

Which of the following best describes an element? (A) A pure substance made of only one type of atom (B) A combination of two or more substances (C) A substance that can be separated by chemical means (D) None of the above

a)

A pure substance made of only one type of atom

b)

A mixture of different elements

c)

A compound made of two or more atoms

d)

A substance that cannot be broken down

13.

Drag and drop the following into the correct categories: Mixture, Compound, Element: Water, Air, Gold, Sugar, Iron.

a)

Mixture: Air; Compound: Water, Sugar; Element: Gold, Iron

b)

Salt

c)

Oxygen

d)

Carbon Dioxide

14.

What is the process of separating a mixture using a filter called?

a)

Evaporation

b)

Filtration

c)

Distillation

d)

Centrifugation

15.

Fill in the blank: A __________ is a substance that cannot be broken down into simpler substances by chemical means.

a)

solution

b)

mixture

c)

compound

d)

element

16.

Which of the following is an example of a heterogeneous mixture? (A) Sugar water (B) Salad dressing (C) Steel (D) Air

a)

Milk

b)

Salad dressing

c)

Salt water

d)

Granite

17.

Fill in the blank: The basic building blocks of matter are __________.

a)

cells

b)

compounds

c)

molecules

d)

atoms

18.

Structure B is

a)

The nucleus

b)

An electron shell

c)

An energy level

19.

Structure C is a(n)

a)

Proton

b)

Neutron

c)

Electron

20.

Structure D is a(n)

a)

Proton

b)

Neutron

c)

Electron

21.

Structure E is a(n)

a)

Proton

b)

Neutron

c)

Electron

22.

Structure E has what charge?

a)

Neutral

b)

Positive

c)

Negative

23.

Structure D has what charge?

a)

Neutral

b)

Positive

c)

Negative

24.

Which of the following correctly defines electrostatic attraction

a)
The force between oppositely charged particles that attracts them to each other.
b)
The force between similarly charged particles that repels them from each other.
c)
The interaction that occurs only in magnetic fields.
d)
The attraction between neutral particles due to gravitational forces.