investigation into the rate of diffusion and surface area

Question 1

what are the two ways the rate of diffusion can be calculated?

Answer 1

distance travelled / time
volume filled / time

Question 2

what is used to investigate the affect of surface are on the rate of diffusion?

Answer 2

agar jelly blocks of different sizes (so different surface areas) which contain phenolpthalein indicator which turns pink when added to alkali

Question 3

outline investigation using agar jelly to see the affect of surface area on the rate of diffusion

Answer 3

immerse the agar blocks (of various sizes) into a solution of NaOH for 10 mins

remove the blocks and and measure the distance that phenolpthalein has become pink using a ruler

Question 4

what does the distance of pink tell you?

Answer 4

the distance of diffusion
the pink phenolpthalein tells you how far NaOH had diffused through the agar jelly