using our resources

Question 1

ceramic

Answer 1

hard, brittle, heat-resistant and corrosion resistance materials

Question 2

composites

Answer 2

consists of two or more materials with different properties that has been combine to produce a material with more desirable properties

Question 3

what are the 2 components for composites materials

Answer 3

• reinforcement - long solid fibres
• matrix - brind the reinforcement tg

Question 4

polymers

Answer 4

large molecules made by monomers

Question 5

polymers properties

Answer 5

• flexible
• easily shaped
• good insulators of heat & electricity

Question 6

LDPE

Answer 6

conditions - moderate temp
- high pressure
- catalyst
properties - flexible but weak
uses - carrier bags

Question 7

HDPE

Answer 7

conditions - low temp/pressure, catalyst
properties - rigid but stronger
uses- drainpipes

Question 8

thermosoftening polymers

Answer 8

• weak inter molecular polymer chains
  that break when heated causing it to
  melt
• remolded into diff shape
• harden again when cooled

Question 9

thermosetting polymers

Answer 9

strong covalent bonds

Question 10

what are the 2 ways to prevent corrosion

Answer 10

barrier methods
sacrificial methods

Question 11

barrier methods

Answer 11

prevent oxygen and water from touching iron
- paint
- oil
- electroplating

Question 12

sacrificial methods

Answer 12

adding a more reactive metal
- (aluminium and zinc)
- they are more reactive so oxidise
rather than the iron

Question 13

corrosion

Answer 13

process by which metals are slowly broken down by reacting with substances in their environment

Question 14

harbour process equation

Answer 14

nitrogen + hydrogen —>
ammonia + heat

Question 15

harbour process conditions

Answer 15

• 450 c
• 200 atm
• iron catalyst

Question 16

harbour process properties

Answer 16

• low temp to favour the forward reaction = higher % yield
• high temp for high rate of reaction
• high temp is expensive

Question 17

what do formulated fertilizers contain

Answer 17

• nitrogen
• phosphorus
• potassium

Question 18

why do plants need nitrogen?

Answer 18

to make amino acids that can be used to produce protein

Question 19

production of phosphorus fertilisers

Answer 19

• mined from phosphorus rock

Question 20

phosphate + nitric acid

Answer 20

phosphoric acid + calcium nitrate

Question 21

phosphate + sulfuric acid

Answer 21

calcium sulfate + calcium phosphate