C15.5 - C15.8 - Using Our Recources (Set A)✔️

Question 1

Word equation for reaction to form ammonia?

Answer 1

Nitrogen + hydrogen — iron catalyst —ammonia

Question 2

What does the Harber process provide?

Answer 2

Harber process provides a way of turning nitrogen in the air into ammonia which is usefull for making fertiliser - process named after German chemist ( Fritz Haber)

Question 3

What are the raw material for the production of ammonia?

Answer 3

-nitrogen from the air
-hydrogen - mainly from natural gas

Question 4

How is the ammonia removed during the harber process?

Answer 4

Removed by cooling the gases so that the ammonia liquefies it can then be seperated from the unreactive nitrogen and hydrogen gas

Question 5

What does it mean the reaction used in the harber process is reversible?

Answer 5

The ammonia gas made breaks down again into nitrogen and hydrogen

Question 6

Which conditions are the harber process carried out in?

Answer 6

-450 degrees
-200 atmospheres pressure
-using an iron catalyst

Question 7

What would a low temperature result in for the reaction to from ammonia?

Answer 7

Slower rate of reaction (and so equalibrium is reached more slowly) higher yeild of ammonia

Question 8

What would a high temperature result in for the reaction to from ammonia?

Answer 8

The forward reaction in the haber process is exothermic so increasing the temperature will move equalibrium the wrong way away from ammonia and towards nitrogen and hydrogen - decreasing the ammonia produced

Question 9

Which pressure would we use for the haber process?

Answer 9

Higher pressure moves the position of equalibrium towards the products and increases the precentage yeild and increases rate or reaction

Question 10

Why is 450 degrees used for the haber process?

Answer 10

It is a compromise between maxium yeild and speed of reaction so it is more economical

Question 11

Why is 200 atmospheric pressure used for haber process?

Answer 11

Pressure is set as high as possible without making the process to expensive as it would require advanced machinery

Question 12

Why is an iron catalysts used in the haber process?

Answer 12

Speeds up the rate of both the forward and reverse reactions by the same amount but does not effect the actual yeild of ammonia produced but decreases time it takes so it is more economical

Question 13

How is the needed nitrogen gas for the haber process obtained?

Answer 13

Nitrogen gas needed extracted from the air

Question 14

How is the needed hydorgen gas for the haber process obtained?

Answer 14

Made by reacting methane gas with steam at very high temperatures

Methane + steam - hydrogen + carbon monixide

Question 15

Issues with the hydrogen being made for the haber process?

Answer 15

• Costs involved in heating the reaction mixture to make super-heated steam
• Price of metahane gas which has to be brought from the gas industry

Question 16

Whta happens to most of the ammonia formend in the haber process?

Answer 16

• Most is changed into compounds of ammonia
• 10% of ammonia made is converted into nitric acid through another process which can then be reacted with more amonia to make ammonium nitrate fertiliser

Question 17

Word equation for the reaction to form ammonium nitrate?

Answer 17

Ammonia + nitric acid - ammonium nitrate

Question 18

How can we make other fertiliser with the ammonia produced through the haber process?Three examples?

Answer 18

Other solid fertiliser salts made by reacting ammonia (alkali) with different acids:
- ammonium nitrate
- ammonium phosphate
- ammonium sulfate

Question 19

Word equation for the neutralisation reaction between ammonia solution and phosphoric acid?

Answer 19

Ammonia + phosphoric acid - ammonium phosphate

Question 20

Word equation for the neutralisation reaction between ammonia solution and sulfuric acid?

Answer 20

Ammonia + sulfuric adid - ammonium sulfate

Question 21

Word equation for the reaction of making hydrogen for the haber process?

Answer 21

Methane + steam - hydrogen + carbon monixide

Question 22

Symbol equation for reaction to make ammonia?

Answer 22

N₂(g) + 3H₂(g) - 2NH₃(g)

Question 23

How is the ammonia made via the haber process seperated?

Answer 23

Ammonia seperated by cooling the gas so that it liquifies

Question 24

What happens to the unreactive hydrogen and nitrogen druing the haber process?

Answer 24

Unreactive nitrogen and hydrogen recycled back into the reaction mixture - they are then re compressed and heated before being returned to the reaction vessel

Question 25

Symbol equation for the reaction to form ammonium nitrate?

Answer 25

NH₃(aq) + HNO₃(aq) - NH₄NO₃(aq)

Question 26

Symbol equation for the neutralisation reaction between ammonia solution and phosphoric acid?

Answer 26

3NH₃(aq) + HPO₄(aq) - (NH₄)₃PO₄(aq)

Question 27

Symbol equation for the neutralisation reaction between ammonia solution and sulfuric acid?

Answer 27

2NH₃(aq) + H₂SO₄(aq) - (NH₄)₂SO₄(aq)

Question 28

What are NPK fertelisers

Answer 28

Fertelisers used to supply nitrogen (N) phosphorus (P) and pottassium (K) to plant - can be added to the land at the same time in mixtures of compounds called NPK ferteliser

Question 29

Why are NPK fertelisers used on crops?

Answer 29

They increase crop yeild and growth

Question 30

What are the two sources of most of the salts in NPK fertelisers?

Answer 30

-some are mined
-most made by reacting acids with bases

Question 31

Why can phosphate rock not be used as a ferteliser?

Answer 31

It can not be used directly on the soil as it is insoluble in water so the rock is treated with acids to make ferteliser salts

Question 32

Where does pottasium come from for making NPK fertelisers?

Answer 32

Potassium comes from potassium salts mined from the ground for use as fertelisers such as potassium chloride and potassium sulfate

Question 33

Where does the nitrogen come from for making NPK fertelisers?

Answer 33

Comes from ammonium made in the haber process which is reacted with acids to make fertelisers such as ammonium nitrate and ammonium sulfate

Question 34

Where does phosphorus come from for making NPK fertelisers?

Answer 34

Source of phosphorus is phosphate rock which is mined and treated with acids to orm fertelisers such as ammonium phosphate