C8(Rates And Equlibrium)

Question 1

What is the formula for rate of reaction

Answer 1

Question 2

What does the gradient of the line tell you about the rate of reaction

Answer 2

-The rate of reaction at that time
-The steeper the gradient the faster the reaction
-to calculate the rate of reaction at a specific time draw the tangent to the curve and calculate its gradient

Question 3

Example of calculating rate of reaction

Answer 3

Question 4

What is collision theory

Answer 4

Particles must collide with a certain minimum amount of energy before they can react

Question 5

What is activation energy

Answer 5

The minimum amount of energy that particles must have in order to react

Question 6

What are the factors that affect the rate of reaction

Answer 6

-concentration
-surface area
-temperature
-pressure
-catalysts

Question 7

How does surface area affect the rate of reaction

Answer 7

If the surface area to volume ratio of any solid increases, this increases the frequency of collisions between reacting particles

Question 8

How does temperature affect the rate of reaction

Answer 8

Increasing the temperature increases the rate of reaction because particles collide more frequently and more energetically

Question 9

How does concentration and pressure affect the rate of reaction

Answer 9

Increasing the pressure or concentration of reactants increases the frequency of collisions of particles

Question 10

What is a catalyst

Answer 10

A substance that changes the rate of reaction by lowering the activation energy
-catalysts are also not used up during the reaction

Question 11

Example of an energy profile using a catalyst

Answer 11

Question 12

What are reversible reactions

Answer 12

The products can react to make the original reactants

Question 13

What is the energy changes for reversible reactions

Answer 13

The forward reaction is exothermic
The backward reaction is endothermic

Question 14

Example of energy transfers in a reversible reaction

Answer 14

Question 15

What happens to the energy transferred in a reversible reaction

Answer 15

The amount of energy transferred to the surroundings when the reaction goes in the forward direction is equal to the energy transferred back when the reaction goes in the backward direction

Question 16

What is dynamic equilibrium

Answer 16

The rate of the forward reaction equals the rate of the backward reaction

Question 17

What happens in a closed system

Answer 17

The rate of the forward and backward reactions is at equilibrium

Question 18

What happens if you change the reaction conditions

Answer 18

Can change the amounts of products and reactants in a reaction mixture at equilibrium

Question 19

How can pressure affect reversible reactions

Answer 19

Increasing the pressure favours the reaction that forms fewer molecules of gas
Decreasing the pressure favours the reaction that forms the greater number of molecules of gas

Question 20

How do you change the relative amount of products formed at equilibrium

Answer 20

By changing the temperature of the reversible reaction

Question 21

How does temperature affect reversible reactions

Answer 21

Increasing the temperature favours the endothermic reaction
Decreasing the temperature favours the exothermic reaction

Question 22

What happens if the forward reaction produces more or less molecules

Answer 22

Question 23

What happens if the forward reaction is exothermic or endothermic

Answer 23