Paper 2 H - SAMPLE SET 1 Q17
17) Some students measured the temperature inside a compost heap.
They also measured the external temperature.
On five occasions they mixed up the compost heap with garden forks.
The graph shows their results.
They also measured the external temperature.
On five occasions they mixed up the compost heap with garden forks.
The graph shows their results.
(a) (i) The compost took 63 days to completely decompose.
Explain how the students could tell this from their graph. [1]
(ii) The rate of temperature increase is greatest before the compost is mixed for the first time. Explain how the rate of temperature change can be calculated. [1]
(b) Compost decomposes more slowly above 60°C or below 30°C.
Use ideas about enzymes and decomposition to explain why this is. [2]
(c) Use the graph to describe how the forking helps to provide the best temperature for decomposition. [2]
(Total for Question 17 = 6 marks)
Explain how the students could tell this from their graph. [1]
(ii) The rate of temperature increase is greatest before the compost is mixed for the first time. Explain how the rate of temperature change can be calculated. [1]
(b) Compost decomposes more slowly above 60°C or below 30°C.
Use ideas about enzymes and decomposition to explain why this is. [2]
(c) Use the graph to describe how the forking helps to provide the best temperature for decomposition. [2]
(Total for Question 17 = 6 marks)