Plastics & Fertilisers

Question 1

What is a polymer?

Answer 1

A long chain molecule made from many small molecules joined together.

Question 2

What is a monomer?

Answer 2

A small molecule that can join with others to form a polymer.

Question 3

What kind of molecules make up addition polymers?

Answer 3

Alkenes (unsaturated hydrocarbons with a double bond).

Question 4

What happens to the double bond during polymerisation?

Answer 4

It opens up and allows the monomers to join together.

Question 5

What is addition polymerisation?

Answer 5

The process of joining unsaturated monomers to form a polymer.

Question 6

What is the only product of addition polymerisation?

Answer 6

The polymer.

Question 7

How do you name an addition polymer?

Answer 7

Add “poly” in front of the monomer name (e.g. propene → poly(propene)).

Question 8

What is a repeating unit in a polymer?

Answer 8

A section of the polymer chain that repeats over and over.

Question 9

What is the Haber process used for?

Answer 9

To make ammonia (NH₃), used in fertilisers.

Question 10

What are the reactants in the Haber process?

Answer 10

Nitrogen (N₂) and hydrogen (H₂).

Question 11

What is the word equation for the Haber process?

Answer 11

Nitrogen + Hydrogen ⇌ Ammonia

Question 12

What kind of reaction is the Haber process?

Answer 12

A reversible reaction.

Question 13

What is the temperature used in the Haber process?

Answer 13

450°C

Question 14

What pressure is used in the Haber process?

Answer 14

200 atm (atmospheres)

Question 15

Why is the temperature a compromise?

Answer 15

Lower temp gives more yield but slower reaction; higher temp is faster but gives less ammonia.

Question 16

What does the iron catalyst do in the Haber process?

Answer 16

Speeds up the reaction but doesn’t affect the yield.

Question 17

Why is unreacted nitrogen and hydrogen recycled?

Answer 17

To reduce waste and improve efficiency.

Question 18

What does the Ostwald process make?

Answer 18

Nitric acid.

Question 19

What raw material does the Ostwald process use?

Answer 19

Ammonia (from the Haber process), air, and water.

Question 20

What catalyst is used in the Ostwald process?

Answer 20

Platinum

Question 21

What are the three main gases formed in the Ostwald process?

Answer 21

Nitrogen monoxide (NO), nitrogen dioxide (NO₂), and nitric acid (HNO₃).

Question 22

How is nitric acid formed in the Ostwald process?

Answer 22

Nitrogen dioxide dissolves in water.

Question 23

What is the purpose of a fertiliser?

Answer 23

To provide nutrients to help plants grow.

Question 24

What are the three essential elements in fertilisers?

Answer 24

Nitrogen, phosphorus, and potassium.

Question 25

Why are fertilisers used instead of manure?

Answer 25

They’re easier to use, don’t smell, and provide specific nutrients.

Question 26

What is the role of nitrogen in plant growth?

Answer 26

Helps plants make proteins and grow faster.

Question 27

Why might plants be missing essential elements?

Answer 27

Previous crops used them up from the soil.

Question 28

What happens when you react ammonia solution with an acid?

Answer 28

You get an ammonium salt and water.

Question 29

What is the word equation for ammonia solution + acid?

Answer 29

Ammonia solution + acid → ammonium salt + water

Question 30

What does nitric acid react with to form nitrates?

Answer 30

A base — e.g. nitric acid + potassium hydroxide → potassium nitrate + water.

Question 31

What happens when ammonia and nitric acid are reacted together?

Answer 31

Ammonium nitrate and water are formed.

Question 32

Why is ammonium nitrate a good fertiliser?

Answer 32

It contains nitrogen from two sources — ammonia and nitric acid.