Elements, Compounds, & Mixtures

– pgs. 245 – 250 & 254 – 261 – KEY

1. /

Definition

/ Examples (list 2)

Element

/ *a pure substance that cannot be separated into simpler substances by physical or chemical means / Carbon
Gold
2. /

Compound

/ *a pure substance composed of two or more Elements that are chemically combined /
Water
Sugar
3. /

Mixture

/ * material made up of two or
more substances that are NOT chemically combined /
Fabric
Pizza

4. Describe the similarities between compounds and mixtures.

Made up of two or more materials

5. Describe the differences between compounds and mixtures.

Compounds cannot be separated by physical means, mixtures can

Compounds have the same amount of each material, mixtures do not

6. Explain the similarities and differences between an element and a compound.

Similarities – cannot be separated by physical means

Differences – element all one material, compound more

than one material

7. Name and briefly explain the two different types of mixtures.

Heterogeneous – mixture in which different materials can

be easily distinguished.

Homogeneous – mixture in which two or more substances

are uniformly spread out.

8. Define physical property.

Characteristic of a material that you can observe without

changing the substance in the material

9. List some specific physical properties.

Answers will vary

10. Define chemical property.

A characteristic of a substance that indicates whether it

can undergo a chemical change.

11. List some specific chemical properties.

Answers will vary

12. Define physical change.

*A change in size, shape or state of matter

*Does not change the identities of the substances in a material

13. Give 1 example of a physical change and describe why it is a physical change.

Answers will vary

14. Define chemical change.

A change of one material to a completely different (new) material

15. Give 1 example of a chemical change and describe why it is a chemical change.

Answers will vary

16. Define the law of conservation of mass.

Matter is neither created nor destroyed during a chemical change

17. Give an example of the law of conservation of mass in action. Describe.

Answers will vary

18. What is the major difference between a chemical change and a physical change?

Chemical change creates a new substance and a physical

change only changes a characteristic of the substance.

19. Why is being flammable a chemical property rather than a physical one?

When something burns it changes to a new substance