Actual Experiment! (Experiment 3- pH of medium)

Conducted on 13th - 14th June 2011.
Start time: 5pm (13-06-2011)
End time: 9.30am (14-06-2011)

Steps:
1) Cut out 6 fabric pieces (5cm x 5cm) from a piece of fabric.
2) Mix 2 teaspoons of ketchup with 1 teaspoon of soya sauce.
3) Place a drop of mixture on each of the fabric pieces.
4) Leave the fabric pieces aside for 2 hours to create a stain.
5) Pour 40ml of freshly-squeezed lemon juice and 100ml of tapwater into a container. Label the set-up- A.
6) Pour 10ml of freshly-squeezed lemon juice and 130ml of tapwater into a container. Label the set-up- B.
7) Pour 140ml of tapwater into a container. Label the set-up- C.
8) Pour 140ml of tapwater into a container and add 1/2 teaspoon of baking soda. Label the set-up D.
9) Stir the mixture of tapwater and baking soda in Set-up D to ensure that the baking soda is fully-dissolved.
10) Pour 140ml of tapwater into a container and add 3 teaspoons of baking soda. Label the set-up E.
11) Stir the mixture of tapwater and baking soda in Set-up E to ensure that the baking soda is fully-dissolved.
12) Add 1/2 teaspoon of detergent into each of the set-ups. Stir all mediums in the set-ups 5 times.
13) Place one piece of stained fabric into each of the set-ups. Leave the remaining fabric piece aside. This will act as the control of the experiment.

14) Leave the set-ups overnight.
15) Remove the 5 fabric pieces from the set-ups and observe the stains left on the fabric pieces. Use the control as a basis for comparison.

Results:

End results (with control as basis for comparison)

 Set-up A- (Medium with pH = 2)
Very little stain has been removed. Although the stain seems a little lighter than the control set-up, almost no stain has been removed.

 Set-up B- (Medium with pH = 4)
Very little stain has been removed. Although the stain seems a little lighter than the control set-up, almost no stain has been removed.

 Set-up C- (Medium with pH = 7)
Least visible stain as compared to all the fabric pieces in other set-ups.

 Set-up D- (Medium with pH = 9)
Stain left is considerably lighter. Second least visible stain.

Set-up E- (Medium with pH = 12)
Very little stain has been removed.








Based on the results, detergent works best in removing stains in neutral - mildly alkaline pH. My hypothesis is then proven correct. (: