Matter/Chemical Change - Section 1

Question 1

What is chemistry?

Answer 1

The science concerned with matter, the properties of matter, and the changes in matter

Question 2

What is matter?

Answer 2

Anything that takes up space and has mass

Question 3

What is a chemical?

Answer 3

Any substance used or produced in a chemical process

All natural materials are produced by chemical processes

Question 4

What is a physical property?

Answer 4

A property that describes the appearance and composition of a substance

Question 5

What are some examples of physical properties? (9)

Answer 5

Melting point
Boiling point
Hardness
Malleability
Ductility
Crystal shape
Solubility
Density
Conductivity

Question 6

What is a chemical property?

Answer 6

A property that describes how a substance interacts chemically with other substances

Question 7

What are some examples of chemical properties? (5)

Answer 7

Reaction with acids
Reaction with water 
Ability to burn
Behaviour in air 
Reaction to heat

Question 8

What is melting?

Answer 8

Occurs when a solid changes to a liquid

Question 9

What is evaporation?

Answer 9

A change from a liquid to a gas

Question 10

What is condensation?

Answer 10

Is the change from a gas to a liquid

Question 11

What is freezing?

Answer 11

A change from a liquid to a solid

Question 12

What is sublimation?

Answer 12

Occurs if a solid goes directly to a gas

Question 13

What is deposition?

Answer 13

Happens when a gas change directly to a solid

Question 14

What are mixtures?

Answer 14

Are composed of two or more different substances whose proportions or ratios may vary

Question 15

What are mechanical mixtures?

Answer 15

Is a type of mixture where you can see the different parts of the mixture

Question 16

What is a solution?

Answer 16

Is a type of mixture where you only see one part

It appears to be one substance

Question 17

What is a suspension?

Answer 17

Is a cloudy mixture in which tiny particles of one substance are held within another substance and could be separated by filtering

Question 18

What is colloid?

Answer 18

Is a cloudy mixture but the suspended particles are so small that they cannot be separated out of the other substance

Question 19

What are pure substances?

Answer 19

They have definite properties that are always the same

Question 20

What are elements?

Answer 20

Pure substances that cannot be broken down into a simpler substances
They are composed of one type of atom

Question 21

What are compounds?

Answer 21

Are pure substances that contain two or more elements in definite proportions
Can only be broken down through chemical reactions

Question 22

What is a physical change?

Answer 22

A change where no new substances are produced

The material may change from state to state or its appearance may be altered in some way

Question 23

What is a chemical change?

Answer 23

A change where one or more new substances are formed with different properties than the starting materials

Question 24

What are some examples of evidence of a chemical change?

Answer 24

Change in colour 
Change in odour 
Heat or light is absorbed or given off
A gas is formed
A solid called a precipitate is formed
Change is difficult to reverse

Question 25

What are some examples of a physical change?

Answer 25

Boiling a solution

Salt dissolving in water

Question 26

What are some examples of a chemical change?

Answer 26

Vinegar and baking soda

Fireworks