UNIT 4- ENERGY AND CHANGES

Question 1

Energy comes in…

Answer 1

Many forms of

Question 2

Energy can be…..into another form of energy

Answer 2

Transformed

Question 3

What is energy?

Answer 3

The ability to do work or effect change

Question 4

What is the unit of measurement for energy?

Answer 4

Joule (J)

Question 5

What is energy transfer?

Answer 5

The movement of energy from one place to another

Question 6

What is energy transformation?

Answer 6

The changing of energy from one form to another

Question 7

What is the law of conservation of energy?

Answer 7

Energy can neither be created or destroyed.

Question 8

What do thermal energy results from?

Answer 8

The particles random movement

Question 9

What are the two factors thermal energy depend on?

Answer 9

• temperature
• number of particles

Question 10

What is the transfer of thermal energy between two environment called?

Answer 10

Heat

Question 11

Heat always passes from the…. Environment to the…… environment

Answer 11

Warmer, cooler

Question 12

Temperature only takes what into account?

Answer 12

Speed particles

Question 13

What do heat depends on?

Answer 13

The speed

Question 14

What do particles depend on?

Answer 14

Mass

Question 15

What do heat expressed in?

Answer 15

Joules (J)

Question 16

What are the three type of changes in matter?

Answer 16

Physical, chemical and nuclear changes

Question 17

When do physical change occur?

Answer 17

When the form or state of a substance is changed.

Question 18

In physical changed the…

Answer 18

Characteristic properties and molecules stayed the same

Question 19

What do the chemical change alters?

Answer 19

The nature of the substance and the molecules

Question 20

Which transformation involves REARRANGING the bonds between atoms and forming molecules?

Answer 20

Chemical change

Question 21

How can we recognize a chemical change has taken place?

Answer 21

• Release of gas
• emissions or absorption of heat
• a change in colour
• the formation of a precipitate

Question 22

How can a chemical change or reaction be represented?

Answer 22

By a chemical Equation

Question 23

In a chemical equation… substances are represented by…

Answer 23

Chemical symbols and formulas

Question 24

What is the law of conservation of mass?

Answer 24

In a chemical change the mass of the reactants is equal to the mass of the products

Question 25

What is Neutralization?

Answer 25

A chemical change in which an acid and base react together to form a salt and water

Question 26

What is combustion

Answer 26

A chemical reaction in which substances combine with oxygen, it always releases energy

Question 27

What are the 3 types of combustion?

Answer 27

• Slow combustion
• Spontaneous combustion
• Rapid combustion

Question 28

Examples of SLOW COMBUSTION

Answer 28

Cut apples turning brown, iron rusting, cellular respiration etc.

Question 29

What is Spontaneous combustion?

Answer 29

Form of combustion in which substances starts burning on their own

Question 30

What is Rapid combustion?

Answer 30

A type of combustion in which substances burn with a flame.

Question 31

How can we recognize combustion?

Answer 31

Heat and light are always produced

Question 32

What is the triangle of fire?

Answer 32

Sets the conditions that must be fulfilled for rapid combustion to take place

Question 33

What is photosynthesis?

Answer 33

A chemical reaction taking place in plants. Plant cells use solar energy to produce Glucose and oxygen from carbon dioxide and water

Question 34

What is Cellular respiration?

Answer 34

A chemical change that uses Glucose and Oxygen to form carbon dioxide and water

Question 35

Where do cellular respiration takes place in?

Answer 35

Every cell of a living animal