Topic 4 - Substances undergo a chemical change when they interact to produce different substances

Question 1

What is a chemical reaction?

Answer 1

When two or more substances merge to create new substances.

Question 2

What is a reactant?

Answer 2

The materials at the start of the reaction.

Question 3

What are evidences of a chemical reaction?

Answer 3

• A colour change
• The formation of an odour
• The composition of a solid or gas
• The release or absorption of heat

Question 4

What does exothmeric mean?

Answer 4

• It releases heat energy

Question 5

What does endothermic mean?

Answer 5

• It absorbs heat energy.

Question 6

What is combustion?

Answer 6

• Chemical reaction which occurs when oxygen reacts with a substance to create a new subsrances and gives off energy.

Question 7

What is corrosion?

Answer 7

• The slow chemical change which happens when oxygen in the air responds with a metal.

Question 8

What is cellular respiration?

Answer 8

• Chemical reaction which takes place in the cells of your body

Question 9

What is the Law of Conservation of Mass say?

Answer 9

• In any chemical reaction, the total mass of the reactants is = to the total mass of the matter which is neither creeated nor destroyed products.

Question 10

What is a closed system?

Answer 10

Where extra materials are not allowed to enter or leave during a chemical reaction.

Question 11

What are Four Factors that can impact the rate of a chemical reaction?

Answer 11

• The Presence of a Catalyst
• The concentration of the reactants
• The temperature of the reactants
• The Surface Area of the reactants

Question 12

What are Catalysts?

Answer 12

They are substances that assist a reaction proceed faster.

Question 13

What does a enzyme do?

Answer 13

Assist the substrates it reacts with to break down.