An experiment was performed as shown in the diagram below. A glass funnel was placed over some water weeds in a beaker of water. A test tube filled with water was carefully inverted over the funnel stem, which was raised above the bottom of the beaker by plasticine.
A small amount of sodium bicarbonate was then added to the water in the set-up, and the apparatus was exposed to sunlight for some hours.
Use this information and the diagrams below to answer questions 1(a) to 1 (c)
Beginning of experiment After some hours
(a) What do X and Y represent in diagram B? [1 mark]
(b) State the aim of the experiment. [1 mark]
(c) Give one reason in each case for the following procedures:
(i) The funnel was placed on blocks of plasticine. [1 mark]
(ii) Sodium bicarbonate was added to the water. [2 marks]
(iii) The set-up was placed in sunlight. [2 marks]
(iv) A glass funnel was used. [1 mark]
(d) (i) Briefly describe what happened in the experiment during the time
interval between diagrams A and B. [4 marks]
(ii) Describe a simple test that would be carried out to identify X in the
diagram. [4 marks]
(iii) Write a balanced chemical equation for the process involved in the experiment. [4 marks]
(e) State five ways in which the process in the experiment is important. [5 marks]
