P2 - 10.7 The Haber Process

Question 1

What is the haber process

Answer 1

The production of ammonia from nitrogen and hydrogen

Question 2

What is the haber process

Answer 2

The production of ammonia from nitrogen and hydrogen

Question 3

What is this process:

N2 + 3H2 <-> 2NH3 (+ heat)

Answer 3

Haber process

Question 4

What is a reversible reaction

Answer 4

Where reactants can be turned into products and products can be turned back into reactant

Question 5

Is the haber process a reversible reaction

Answer 5

Yes

Question 6

What temperature is the haber process done at

Answer 6

450°C

Question 7

What pressure is the haber process done at

Answer 7

200 atm (atmospheres)

Question 8

What type of catalyst is used in the haber process

Answer 8

Iron catalyst

Question 9

True or False: the haber process is one of the most important reactions in the world

Answer 9

True

Question 10

In the haber process what is the product ammonia used for

Answer 10

To make nitrogen based fertilisers

Question 11

What do nitrogen based fertilisers do

Answer 11

Helps increase food production

Question 12

Where do we get nitrogen from for the haber process

Answer 12

The air (makes up 78%)

Question 13

How much nitrogen is in the air

Answer 13

78%

Question 14

How do we get hydrogen for the haber process

Answer 14

We have to make it from hydrocarbons like methane

Question 15

Is the haber process endothermic or exothermic

Answer 15

Exothermic (releases energy to surroundings)

Question 16

What is the first step in the haber process

Answer 16

Feeding the nitrogen and hydrogen into the top left where they can mix together

Question 17

What is the first area of the haber process called

Answer 17

Reaction vessel

Question 18

In the reaction vessel what is the temperature

Answer 18

450°C

Question 19

In the reaction vessel what is the pressure

Answer 19

200atm (atmospheres)

Question 20

Where is the iron catalyst in the haber process

Answer 20

Inside the reaction vessel in the middle of the

Question 21

True or False: gases can freely pass through the iron catalyst in the haber process

Answer 21

True

Question 22

Whilst inside the reaction vessel what does hydrogen and nitrogen form when reacted together

Answer 22

Ammonia

Question 23

True or False: in the haber process it is a compound formed in the reaction vessel

Answer 23

False it is a mixture

Question 24

What elements can you find in the reaction vessel during the haber process

Answer 24

Ammonia
Nitrogen
Hydrogen

Question 25

Does ammonia have a high or low boiling point

Answer 25

Fairly low

Question 26

What is the second step of the haber process

Answer 26

Nitrogen and hydrogen mix together to form ammonia

Question 27

What is the third step of the haber process

Answer 27

Ammonia goes through a pipe into an area called the condensor, which condenses the gas turning into a liquid Hydrogen and nitrogen don’t condense due to low boiling points and are recycled back around to the reaction vessel

Question 28

What happens in the condensor

Answer 28

- gaseous ammonia is condensed into liquid ammonia due to low BP - hydrogen and nitrogen stay in gaseous form and are recycled back into reaction vessel due to low BP

Question 29

Is the condenser hot or cold

Answer 29

Cold

Question 30

What is the symbol equation for the haber process

Answer 30

N2 + 3H2 <-> 2NH3 (+ heat) -> Iron catalyst 450°C 200atm

Question 31

What 3 things do we need to consider when looking at why the temperature in the haber process is 450°C and the pressure is 200atm

Answer 31

% yield Rate of reaction Cost

Question 32

Why is the temperature in the haber process at 450°C

Answer 32

- because it is exothermic, it needs a low temp to favour forward reaction to achieve higher % yield - it needs a higher temperature to increase rate of reaction as particles need lots of kinetic energy in order to react - chosen as a compromise as it produces a lower yield but a higher rate of reaction - generating heat is expensive so using a high temp is very costly

Question 33

Why is the pressure in the haber process at 200atm

Answer 33

- to achieve a higher % yield by having a high pressure (means there are fewer molecules of product than there are reactants) - pushes equilibrium to the right - higher pressure increases rate of reaction, higher pressure means particles collide more frequently - high pressure is limited by cost and safety as maintaining a high pressure is costly and if it goes wrong it can be very dangerous

Question 34

What is the word equation for the haber process

Answer 34

Nitrogen + hydrogen <-> ammonia