4.2 - SPECIMEN SET B1 Q7 Answers
7) A student investigated the effect of pond organisms on the amount of carbon dioxide in their surroundings.
The student set up six boiling tubes as shown in Figure 6.
They were left for 2 days.
Each boiling tube contained pond water with an indicator.
The indicator was pink at the start of the investigation.
The student set up six boiling tubes as shown in Figure 6.
They were left for 2 days.
Each boiling tube contained pond water with an indicator.
The indicator was pink at the start of the investigation.
- If the amount of carbon dioxide in the water increased the indicator turned yellow.
- If the amount of carbon dioxide in the water decreased the indicator turned purple.
7.1) What is the purpose of boiling tube A? [2 marks]
7.2) In which boiling tube would the indicator be the most yellow after 2 days?
Explain your answer. [3 marks]
Boiling tube ________________________
Explanation ________________________
7.3) The colour of the indicator in boiling tube C had not changed after 2 days.
Suggest why. [1 mark]
(Total for Question 7 = 6 marks)
7.2) In which boiling tube would the indicator be the most yellow after 2 days?
Explain your answer. [3 marks]
Boiling tube ________________________
Explanation ________________________
7.3) The colour of the indicator in boiling tube C had not changed after 2 days.
Suggest why. [1 mark]
(Total for Question 7 = 6 marks)
Answers
