C15 - Using our resources

Question 1

What is corrosion?

Answer 1

The destruction of a material through reactions with substances in the environment

Question 2

What physical barriers can be used to protect against corrosion?

Answer 2

Grease, paint, thin metal

Question 3

What is sacrificial protection?

Answer 3

Adding a more reactive metal to the surface of a material. The more reactive one will be damaged instead of the other material.

Question 4

How is rust formed?

Answer 4

A reaction between iron, oxygen and water

Question 5

Composition, properties and uses of bronze

Answer 5

• Copper and tin
• Resistant to corrosion
• Statues, decor, ship propellers

Question 6

Composition, properties and uses of brass

Answer 6

• Copper and zinc
• Hard
• Door fittings, taps, instruments

Question 7

Composition, properties and uses of gold alloys

Answer 7

• Gold and copper/silver/zinc
• Pretty, corrosion resistant, hard (depending on carat)
• Jewellery

Question 8

Composition, properties and uses of high carbon steel

Answer 8

• Iron and 1-2% carbon
• Strong but brittle
• Cutting tools and metal presses

Question 9

Composition, properties and uses of low carbon steel

Answer 9

• Iron and <1% carbon
• Soft and easy to shape
• Cars, machinery, ships, structural steel

Question 10

Composition, properties and uses of stainless steel

Answer 10

• Iron with chromium and nickel
• Corrosion resistant, hard
• Cutlery and plumbing

Question 11

Composition, properties and uses of aluminium alloys

Answer 11

• Aluminium and something
• Low density
• Aircraft and military

Question 12

Composition, properties and uses of soda-lime glass

Answer 12

• Heated sand, sodium carbonate and limestone
• Transparent, brittle
• Everyday glass objects

Question 13

Composition, properties and uses of borosilicate glass

Answer 13

• Heat sand and boron trioxide
• High mp
• Oven glassware, lab glassware

Question 14

Composition, properties and uses of clay ceramics

Answer 14

• Wet clay heated in furnace
• Hard, brittle, corrosion resistant, easy to shape
• Pottery, bricks, plumbing fixtures

Question 15

What do the properties of polymers depend on?

Answer 15

The monomer used and the conditions under which they reacted

Question 16

How are low density polymers formed?

Answer 16

• Addition polymerisation
• High pressure
• Small amount of oxygen
• Branched polymer chains can’t pack together

Question 17

How are high density polymers formed?

Answer 17

• Addition polymerisation
• 50 degrees C
• Catalyst
• Chains are straight so can pack together

Question 18

What are the two differences between thermosetting and thermosoftening polymers?

Answer 18

• Thermosetting have cross linking covalent bonds, thermosoftening don’t
• Thermosetting don’t melt when heated, thermosoftening do

Question 19

What is a composite?

Answer 19

Material made from one main material and fragments of others added. e.g plywood

Question 20

What is a NPK fertiliser?

Answer 20

A formulation containing soluble compounds of nitrogen, potassium and phosphorus

Question 21

How are fertilisers made in a lab?

Answer 21

• Small quantities
• Batch process
• Glass apparatus
• Slow

Question 22

How are fertilisers made in industry?

Answer 22

• Large quantities
• Continuous process
• Stainless steel apparatus
• Fast