1.
State what is meant by a finite resource.
[1 mark]
- will run out / used faster than it forms
JD SCIENCE
Unit 6 answers — C6 Global challenges
Indicative marking points. Award marks for equivalent scientific or mathematical wording. Do not issue this sheet with the student worksheet.
2.
State what is meant by a renewable resource.
[1 mark]
- can be replaced as fast as it is used
3.
State what is meant by potable water.
[1 mark]
- water safe to drink
4.
State what is meant by desalination.
[1 mark]
- removing salt from seawater
5.
State what is meant by waste-water treatment.
[1 mark]
- screening, sedimentation, anaerobic digestion, sterilising
6.
State what is meant by life-cycle assessment.
[1 mark]
- impact of a product from raw materials to disposal
7.
State what is meant by recycling metals.
[1 mark]
- melting and remaking
8.
State what is meant by phytomining.
[1 mark]
- plants absorb metal ions from soil
9.
State what is meant by bioleaching.
[1 mark]
- bacteria extract metals from ores
10.
State what is meant by an alloy.
[1 mark]
- mixture of a metal with other elements
11.
Grace is asked about a finite resource in a OCR Chemistry paper.
(a) [2 marks]
- fossil fuels, metal ores
(b) [3 marks]
- need recycling
12.
Grace is asked about a renewable resource in a OCR Chemistry paper.
(a) [2 marks]
- timber if replanted, wool
(b) [3 marks]
- more sustainable
13.
Grace is asked about potable water in a OCR Chemistry paper.
(a) [2 marks]
- not necessarily pure H₂O
(b) [3 marks]
- filtered and sterilised
14.
Grace is asked about desalination in a OCR Chemistry paper.
(a) [2 marks]
- distillation or reverse osmosis
(b) [3 marks]
- high energy cost
15.
Grace is asked about waste-water treatment in a OCR Chemistry paper.
(a) [2 marks]
- before release
(b) [3 marks]
- reduces disease
16.
Grace is asked about life-cycle assessment in a OCR Chemistry paper.
(a) [2 marks]
- energy, water, waste
(b) [3 marks]
- used to compare bags / bottles
17.
A tap produces 8 dm³/min. Volume in 5 minutes
[3 marks]
- Final answer: 40 dm³
18.
Recycling aluminium uses 5% of the energy of extraction. Energy saved as a percentage
[3 marks]
- Final answer: 95%
19.
A bottle has a mass of 40 g. How many bottles in 2.0 kg
[3 marks]
- Final answer: 50
20.
Salt water is 3.5% salt. Mass of salt in 200 g of seawater
[3 marks]
- Final answer: 7.0 g
21.
A filter removes 92% of particles. Particles remaining from 250 mg
[3 marks]
- Final answer: 20 mg
22.
Cost of desalination is £1.20 per m³. Cost for 15 m³
[3 marks]
- Final answer: £18.00
23.
Grace carries out a OCR-style required practical linked to using resources and water. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: the independent variable for this topic
- Dependent: the measured outcome
(b) [2 marks]
- keep all other variables constant
- so the test is fair / only one variable is changed
(c) [2 marks]
- repeat and calculate a mean / use a tighter method
24.
Grace carries out collecting valid data for using resources and water. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: a chosen factor
- Dependent: a quantitative measurement
(b) [2 marks]
- calibrated instrument
- so the test is fair / only one variable is changed
(c) [2 marks]
- systematic error from zero error
25.
Grace carries out drawing a graph for using resources and water. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: x-variable
- Dependent: y-variable
(b) [2 marks]
- same scale / same apparatus
- so the test is fair / only one variable is changed
(c) [2 marks]
- not drawing a line of best fit through the trend
26.
Grace carries out evaluating a method about using resources and water. This is a typical OCR required-practical style question.
(a) [2 marks]
- Independent: method change
- Dependent: precision / accuracy
(b) [2 marks]
- same sample size
- so the test is fair / only one variable is changed
(c) [2 marks]
- too few repeats
27.
Compare a finite resource with a renewable resource.
[4 marks]
- will run out / used faster than it forms
- can be replaced as fast as it is used
- give one linked difference
28.
Compare a renewable resource with potable water.
[4 marks]
- can be replaced as fast as it is used
- water safe to drink
- give one linked difference
29.
Compare potable water with desalination.
[4 marks]
- water safe to drink
- removing salt from seawater
- give one linked difference
30.
Compare desalination with waste-water treatment.
[4 marks]
- removing salt from seawater
- screening, sedimentation, anaerobic digestion, sterilising
- give one linked difference
31.
Apply your knowledge of recycling metals to this situation: saves energy vs extraction
[3 marks]
- saves energy vs extraction
32.
Apply your knowledge of phytomining to this situation: burn plants to get ash
[3 marks]
- burn plants to get ash