Question

(a) What is the apparatus shown below called? State its purpose.

(b) State the use of:
(i) Capillary tube
(ii) Scale
(iii) Water reservoir

(c) What happens to the movement of air bubbles if the apparatus is kept:
(i) in sunlight;
(ii) in darkness;
(iii) in front of a fan? [5 MARKS]

Answer 1

a) 2 Marks
b) 1.5 Marks
c) 1.5 Marks

(a) The apparatus is called a potometer. Its purpose is to find the rate of transpiration.

(b)
(i) A capillary tube is used to connect the bottle with the beaker containing water.
(ii) Scale is used to measure the distance traveled by the air bubble, i.e. the volume of water transpired.
(iii) Water reservoir is used to reset the air bubble in the apparatus.

(c)
(i) In sunlight, the air bubbles move rapidly.
(ii) In darkness, the air bubbles do not show any movement.
(iii) In front of a fan, the air bubbles show faster movement as transpiration increases with the velocity of wind.