Resources

Question 1

How is potable water formed from fresh water?

Answer 1

Choose source of fresh water e.g a river
Pass water through filter beds to remove suspend particles
Water is then sterilised to kill microbes

Question 2

Explain the process of phytomining

Answer 2

Plants containing the metal compound are grown
The plants concentrate the metal in the tissue
They are then harvested and burned
Ash contains relatively high concentration of the metal compound

Question 3

Explain the process of bioleaching

Answer 3

Bacteria are mixed with the low grade ore
The bacteria carry out chemical reactions to produce a leachate which contains the metal compound

Question 4

Explain a life cycle assessment

Answer 4

Raw materials must be extracted and made into a polymer which requires lots of energy
Now we manufacture, package and transport the product
We now asses the environmental impact during the products life time
And then during its disposal

Question 5

Formation of soda-lime glass

Answer 5

Mix sand, sodium carbonate and limestone
Heat in furnace until it melts
Cools and solidifies into chosen shape

Question 6

How can we change the properties of a polymer?

Answer 6

Change the reaction temperature
Change the reaction pressure
Change the catalyst

Question 7

Structure of thermosoftening polymers

Answer 7

Weak intermolecular forces between polymer strands

Question 8

Structure of thermosetting polymers

Answer 8

Contain strong cross links between polymer strands

Question 9

Conditions for the harbour process?

Answer 9

Iron catalyst
450 degrees C
200 atm

Question 10

Harbour process equation?

Answer 10

Nitrogen + hydrogen —> ammonia

Question 11

Harbour process equation?

Answer 11

Nitrogen + hydrogen —> ammonia

Question 12

How do we obtain nitrogen for NPK fertilisers

Answer 12

The nitrogen is mainly ammonium nitrate
We make ammonia from harbour process
And use ammonia to produce nitric acid

Question 13

How do we obtain potassium for NPK fertilisers?

Answer 13

They usually come from potassium chloride or potassium sulfate
Mined from the ground

Question 14

How do we obtain phosphorus from phosphate rock and nitric acid?

Answer 14

This produces phosphoric acid and calcium nitrate
Neutralise the acid wirh ammonia
To produce ammonium phosphate which we can use

Question 15

How to obtain phosphorus from phosphate rock and sulfuric acid?

Answer 15

Produces calcium phosphate and calcium sulfate
This is called single superphosphate
Which we can use

Question 16

How to obtain phosphorus from phosphate rock and phosphoric acid?

Answer 16

This produces triple superphosphate
Which we can use