SCIENCE TEST 2-28-25

Question 1

Activation Energy:

Answer 1

The minimum amount of energy needed to get a chemical reaction started

Question 2

What is the difference between endothermic and exothermic?
Endothermic reaction

Answer 2

A reaction that absorbs energy in the form of heat (temperature decrease)

Question 3

Exothermic reaction:

Answer 3

A reaction that releases energy in the form of heat (temperature increases)

Question 4

What is the difference in the amount of energy in the reactants and products?
Exothermic reaction:

Answer 4

the products have less energy than the reactants so energy is released as heat; Creation of Heat

Question 5

What is the difference in the amount of energy in the reactants and products?
Endothermic reaction:

Answer 5

Reactants have less energy than products, so energy is absorbed from the surroundings; Creation of Cold

Question 6

What can change the amount of activation energy needed? What would happen to your graph?

Answer 6

You can use a catalyst. If the activation energy is the same and one reaction has a higher peak than they used a catalyst

Question 7

Catalyst

Answer 7

A material that increases the rate of a reaction by lowering the activation energy

Question 8

What affects the rate of a chemical reaction?
Can you explain each?
Surface Area

Answer 8

If you break the solid into smaller pieces, more particles are exposed and the reaction happens faster

Question 9

Temperature

Answer 9

When you heat a substance its particles move faster
Faster moving particles increase the reaction rate in 2 ways

Question 10

Concentration

Answer 10

is the amount of a substance in a given volume

Question 11

Enzyme:

Answer 11

Biological catalyst that lowers the activation energy of reactions in cells

Question 12

Inhibitor
Example:

Answer 12

A material used to slow down a reaction
Preservatives added to food

Question 13

What are the three parts of the fire triangle?

Answer 13

Heat, Oxygen, and Fuel

Question 14

How can you control a fire?

Answer 14

Stone, Concrete, Steel, can all prevent a fire from spreading

Question 15

Fight a fire?

Answer 15

You can use water or fire extinguisher to stop the fire

Question 16

Prevent trouble?

Answer 16

Alarms, sprinklers fire extinguisher, can all help prevent trouble

Question 17

What creates a surface on which reactions can take place?

Answer 17

Enzyme

Question 18

What can slow down a reaction

Answer 18

Inhibitor

Question 19

Which will react faster alka-seltzer tablet, or crushed up

Answer 19

Crushed up, because each particle can react with the water it is being dissolved in

Question 20

Wildfire –

Answer 20

removing fuel

Question 21

When a chemical reaction gives off heat what kind of reaction is it?

Answer 21

Exothermic

Question 22

In an endothermic reaction heat is

Answer 22

Absorbed

Question 23

In the graph if you used catalyst

Answer 23

the amount of activation energy would decrease