Kinetics and equilibrium

Question 1

What is collision theory

Answer 1

The number of particles colliding per second

Question 2

What is activation energy

Answer 2

The minimum amount of energy needed to start a reaction

Question 3

What factors can affect chemical reactions

Answer 3

Increasing concentration of a solution

Increasing the surface area

Increasing temperature

Using a catalyst

Increasing pressure of a gas

Question 4

How does increasing the temperature increase the rate of reaction

Answer 4

So molecules have energy higher than the activation energy so when they collide reaction occurs

Question 5

How does increasing concentration of a solution increase rate of reaction

Answer 5

As there are more molecules meaning they are closer together so frequently of collision increases

Question 6

Describe the effect of increasing surface area

Answer 6

More particles are available to collide

Question 7

What is a catalyst and how does it work

Answer 7

It’s a substance that speeds to a reaction without being used to it lowers activation energy and provides an alternative pathway

Question 8

State what’s on y and X axis on a maxwell boltzmann graph

Answer 8

Y axis is fraction of particles with energy

X axis -energy

Question 9

State the effect of temperature on a maxwell Boltzmann graph

Answer 9

The curve peak moves to right and is lower

Question 10

Give some examples of catalyst used

Answer 10

Platinum and rhodium

Question 11

What is meant by dynamic equlilbrium

Answer 11

The rate of foward and back reactions is equal and concentrations are constant

Question 12

What is le chatlier principle

Answer 12

When the conditions on system in equilibrium are changed the equilibrium will move to oppose the change

Question 13

If concentration in a dynamic equilibrium is changed what will the system do

Answer 13

The system will oppose the change by shifting to the side that hadnt been in effected by concentration change thereby increasing its yield

Question 14

If the forward reaction is endothermic and the temperature is increased in a dynamic equilibrium what will occur

Answer 14

The system will oppose the change and will reduce the temperature thereby favouring the endothermic reaction

Question 15

If the temperature is reduced in a dynamic equilibrium what will happen

Answer 15

The system will oppose the change by increasing the temperature and will favour the exothermic reaction

Question 16

What effect does the addition of a catalyst have on equilibrium

Answer 16

It has no impact on the position but it reduces the time taken to reach equilibrium

Question 17

If the pressure in an equilibrium is increased what will the system do

Answer 17

It will favour the side with the fewest number of miles

Question 18

Give the conditions in the Haber process and state the reason why they are like that

Answer 18

Low temperature as the foward reaction is expthermic if temperature is lowered the equilibrium will shift to the exothermic direction so more ammonia is used

High pressure- fewer number of moles on the right hand side so increase in pressure means equilibrium willl shift to the right

Catalyst - iron catalyst is used

Question 19

Why are compromise conditions used in the haber process

Answer 19

As to low temperature means rate of reaction would be to low

High pressure isn’t use as it’s to expensive and requires expensive equipment

Both conditions are used as they give a reasonable yield at a reasonable cost

Question 20

What are benefits of using a catalyst in reactions like the haber process

Answer 20

Means reactions can be done at a Lower temperature

Gives fewer unwanted products