Unit B Section 4

Question 1

______are shown on the left side of the arrow in a chemical reaction

Answer 1

reactants

Question 2

________are shown on the right side of the arrow in a chemical reaction

Answer 2

Products

Question 3

Evidence that a chemical reaction occurred?(4)

Answer 3

Change in colour,odour,formation of solid or gas, release/absorption of energy

Question 4

Reaction that absolves heat energy

Answer 4

Endothermic

Question 5

Reaction that releases heat energy

Answer 5

Exothermic

Question 6

which chemical reaction is melting an example of

Answer 6

Endothermic

Question 7

what is lighting a fire an example of

Answer 7

Exothermic reaction

Question 8

3 chemical changes involving oxygen?

Answer 8

Combustion, corrosion and cellular respiration

Question 9

When oxygen reacts with a substance to form a new substance and release energy

Answer 9

Combustion

Question 10

Occurs when oxygen reacts with metal (rust)

Answer 10

Corrosion

Question 11

cells in the body; food reacts with oxygen to produce water, energy and CO2

Answer 11

Cellular respiration

Question 12

what are reactions

Answer 12

chemicals that react to form products

Question 13

Law of conservation of mass?

Answer 13

Matter is neither created or destroyed

Question 14

Who is credited the discoverer for the law of conservation of mass

Answer 14

Antoine Laurent Lavoisier

Question 15

In a chemical change, the total mass of the new substance is always the _________ as the mass of the _________ substances

Answer 15

Same, original

Question 16

What is a closed system?

Answer 16

Nothing is allowed to escape, allowing us to weigh everything

Question 17

What is an open system ?

Answer 17

Materials may escape, like gas

Question 18

What is the rate of the reaction?

Answer 18

The speed that a chemical reaction will take place

Question 19

_____ things can speed up/ slow down the rate of a reaction

Answer 19

4

Question 20

Things that affect the rate of a reaction

Answer 20

1. Presence of a catalyst
2. Concentration of reactants
3. Surface area of reactants
4. temperature of reactants

Question 21

2 properties of catalysts

Answer 21

• not consumed during chemical reactions

- speed up reactions

Question 22

What are ‘catalysts’ in the human body?

Answer 22

Enzymes

Question 23

Example of an enzyme?

Answer 23

Salivary amylase

Question 24

The _________ the concentration of the _______ the faster the reaction.

Answer 24

Greater, reactants

Question 25

The __________ the temperature of the __________ the slower the reaction

Answer 25

Lower,reactants

Question 26

The __________ the surface area of the _________ the faster the reaction

Answer 26

Larger, reactants