Demonstration of the Relationship between the Surface Area to Volume ratio on the rate of Diffusion
Introduction:
The surface area to volume ratio determines the rate of diffusion, the larger it is the faster nutrients will diffuse. Phenolphthalein acts as an acid-base indicator, turning pink in bases like NaOH and being colorless in acids like HCl. Using agar blocks as cells, a model was made to measure the rate of diffusion of different sized pink agar blocks changing to colorless ones.
Procedure:
The agar blocks, pink because it was made with phenolphthalein and NaOH were cut into three different sizes. Then each block was immersed in HCl for a color change. Using a timer the rate of diffusion was measured until each block’s color changed to colorless.
Results:
Surface Area (cm) Volume (cm) Surface area: volume ratio Time (mins.)
Small 2.64 cm2 0.15 cm3 17.6 10 mins
Medium 10.36 cm2 1.20 cm3 8.63 16 mins
Large 5.49 cm2 0.55 cm3 10.00
Discussion:
The model of the agar blocks proved that the larger the surface area to volume ratio is …show more content…
The solutions were glucose and water, sucrose and water, starch and water, and water and NaCl. The last pair of solutions was water and water acting as the control. Before the dialysis tubings were immersed in the solutions each’s initial weight was measured and recorded. Then it was immersed completely in each solution and was left for 30 minutes. Afterwards the dialysis tubings were taken out of the solutions dried and final weight was measured and recorded.
Results:
Initial weight (g) Final weight (g) % change in weight Glucose H2O
10.1 g
11.5 g
13.86 % Sucrose H2O
10.4
Introduction:
The surface area to volume ratio determines the rate of diffusion, the larger it is the faster nutrients will diffuse. Phenolphthalein acts as an acid-base indicator, turning pink in bases like NaOH and being colorless in acids like HCl. Using agar blocks as cells, a model was made to measure the rate of diffusion of different sized pink agar blocks changing to colorless ones.
Procedure:
The agar blocks, pink because it was made with phenolphthalein and NaOH were cut into three different sizes. Then each block was immersed in HCl for a color change. Using a timer the rate of diffusion was measured until each block’s color changed to colorless.
Results:
Surface Area (cm) Volume (cm) Surface area: volume ratio Time (mins.)
Small 2.64 cm2 0.15 cm3 17.6 10 mins
Medium 10.36 cm2 1.20 cm3 8.63 16 mins
Large 5.49 cm2 0.55 cm3 10.00
Discussion:
The model of the agar blocks proved that the larger the surface area to volume ratio is …show more content…
The solutions were glucose and water, sucrose and water, starch and water, and water and NaCl. The last pair of solutions was water and water acting as the control. Before the dialysis tubings were immersed in the solutions each’s initial weight was measured and recorded. Then it was immersed completely in each solution and was left for 30 minutes. Afterwards the dialysis tubings were taken out of the solutions dried and final weight was measured and recorded.
Results:
Initial weight (g) Final weight (g) % change in weight Glucose H2O
10.1 g
11.5 g
13.86 % Sucrose H2O
10.4