Unit 2

Question 1

What is the particle theory?

Answer 1

1. All matter is made up of tiny particles called atoms
2. All particles of one substance are the same
   3-particles are always moving
   4- particles are separated by empty spaces
   5- particles are attracted to each other

Question 2

Matter

Answer 2

Is anything that has mass and takes up space

Question 3

Pure substances

Answer 3

Consists of only one type of particle 

Question 4

Mixtures

Answer 4

Consists of more than one type of particle 

Question 5

Elements 

Answer 5

Are indivisible and cannot be chemically broken down

Question 6

Compounds 

Answer 6

Are made up of elements and can be broken down into elements 

Question 7

Mechanical mixture 

Answer 7

Have more than one part visible

Question 8

 Solutions

Answer 8

Have only one part visible 

Question 9

Physical property 

Answer 9

A description that describes as substances properties

Question 10

Chemical property 

Answer 10

A description that describes a substance as it reacts to produce a new substance

Question 11

State 

Answer 11

What state the substance is in either solid liquid or gas ex the bubble in pop are gas.

Question 12

Clarity

Answer 12

How well light passes through an object.

Question 13

Conductivity 

Answer 13

How well a substance let’s heat or electric charge pass through it ex copper is being used in wiring because it has good conductivity 

Question 14

Solubillity

Answer 14

How well, a substance dissolves another substance ex blender has a high sole Bility in coffee 

Question 15

Luster

Answer 15

How well, the surface of a substance reflects light ex aluminum foil is very shiny and has luster

Question 16

Texture 

Answer 16

How the surface of a substance feel, smooth, rough or soft 

Question 17

Hardness

Answer 17

How resistant a substance is to being scratched or dented 

Question 18

Malleability

Answer 18

How well a substance can be bent example aluminum foil is malleability 

Question 19

Ductility

Answer 19

How well a substance can be drawn into a wire ex copper is very ductile 

Question 20

Form

Answer 20

Whether a solid is crystalline crystal lake or no organized shape

Question 21

Viscosity 

Answer 21

How thick a substance is or how easily it pours

Question 22

Density 

Answer 22

How compact a substance is ex a rock is more dense than water, so it sinks 

Question 23

Melting point 

Answer 23

Chances from a solid to a liquid water 0

Question 24

Boiling point 

Answer 24

Where the substance turns from a liquid to a gas water 100

Question 25

Brittleness 

Answer 25

How easily a substance breaks

Question 26

Combustibility 

Answer 26

When something catches fire or burns in air combustion needs a fuel, oxygen and energy. substance plus oxygen carbon dioxide plus water plus heat 

Question 27

Corrosion esion or reaction with oxygen 

Answer 27

When a substance combines with oxygen to form a new substance 

Question 28

Reaction with acid 

Answer 28

A neutralization reaction is when an acid and a base react to form water and a salt example :magnesium metal reacts with acid to produce gas bubbles gold does not react with acid 

Question 29

Reaction with other substances 

Answer 29

A substance changes when it is exposed to another substance 

Question 30

Decomposition

Answer 30

Decomposition Reaction - Definition, Types, Examples, Uses
A decomposition reaction can be defined as a chemical reaction in which one reactant breaks down into two or more products.

Question 31

Physical change 

Answer 31

Changes in matter that will not produce new substances changes only the shape or state of a substance most, but not all are easily reversed. Examples, sugar, dissolved in water. 

Question 32

Chemical change 

Answer 32

Change in matter, that will produce new substances the new substances have new principles example iron, plus oxygen - iron oxide witch is rust product

Question 33

Evidence of chemical change 

Answer 33

Change in colour
Bubbles or gas released
A precipitate is formed
Heat or light is givin off
The change canning be reversed