C15 - Using our Resources

Question 1

How is soda-lime glass made?

Answer 1

Heating a mixture of limestone, sand and sodium carbonate

Question 2

Give three examples of composite materials.

Answer 2

• Fibreglass
• Carbon fibre
• Concrete
• Wood

Question 3

Describe the differences in properties of low density poly(ethene) and high density poly(ethene).

Answer 3

LDP:
- Moderate temperature at high pressure with a catalyst
- Flexible
- Polymer chains randomly branched and cannot pack closely together
HDP:
- Lower temperature and pressure with different catalyst
- More rigid
- Straighter polymer chains packed more closely together

Question 4

Name two elements that can be added to iron to make stainles steel.

Answer 4

• Carbon
• Chromium
• Sometimes nickel

Question 5

What two metals is bronze made of?

Answer 5

• Copper

- Tin

Question 6

Give two uses of brass.

Answer 6

(Copper + Zinc)

• Water taps
• Door fittings

Question 7

What two substances does iron react with when it rusts?

Answer 7

• Oxygen
• Water
  (it is oxidised)
  (makes hydrated iron (III) oxide

Question 8

Aluminium objects can corrode. Why is aluminium not completely destroyed by corrosion?

Answer 8

• Aluminium oxide that is formed doesn’t flake away

- Instead creates protective layer that stops any further reaction taking place

Question 9

Suggest three ways of making a barrier that can be used to protect an iron object from rusting.

Answer 9

• Painting
• Coating with plastic
• Electroplating (coating it with another metal that won’t corrode away)
• Oiling/Greasing

Question 10

Suggest one metal that can be used in the sacrificial method to prevent rusting.

Answer 10

(Placing a more reactive metal with the iron; water and oxygen react with this instead of with the iron)

• Zinc
• Magnesium

Question 11

What is the balanced symbol equation for the Haber process?

Answer 11

• N(2) + 3H(2) –(reversible)-> 2NH(3) (+ heat)

- Nitrogen + hydrogen –(reversible)-> ammonia

Question 12

From what source is the hydrogen used in the Haber process obtained?

Answer 12

Reacting methane with steam to form hydrogen and carbon dioxide

Question 13

What happens to the unused hydrogen and nitrogen in the Haber process?

Answer 13

They are recycled so nothing is wasted

Question 14

What three elements are present in NPK fertilisers?

Answer 14

• Nitrogen
• Phosphorus
• Potassium

Question 15

What substances can be reacted together to produce the following:

a) Ammonium nitrate
b) Phosphoric acid and calcium nitrate
c) Calcium phosphate only

Answer 15

a) Ammonia and nitric acid
b) Nitric acid
c) Phosphoric acid