Problem: What is the effect of different detergents on surface tension of distilled, boiled, and tap water?

Hypothesis: Our theory is that the effect of the different detergents on the surface tension of distilled, boiled, and tap water will decrease. We think that the surface tension of distilled, boiled and tap water is somewhat different causing the effect of the different detergents to differ.

Materials:

3-250ml types of water (all room temperature): *boiled *distilled * tap

4 dishwashing detergent: *sunlight *palmolive *dove *ivory

Dropper

Stirring rod/spoon

Button

30cm long of thread

12 transparent cups

Camera (to take picture during the experiment)

Method:

1. Fill four cups with 250ml boiled water.

2. Put thread in the button (it will inform us the effect of the different detergents in the water) so when the button sinks you can get it out easily.

3. Holding the thread, gently lower the button in the water.

4. Make sure that the button floats. (if it doesn't, find another one that does)

5. Using the dropper, place a drop of detergent into the water.

6. Stir the water with the stirring rod.

7. Carefully lower the button and rest it on the waters surface.

Observation:

Distilled

*Dove- Bubbles started to form at the top of the water around the 11th drop. On the 44th drop the water began to resemble the detergents colour. On the 57th drop the watercolour got hasty. The level of the water rinsed slightly. The buttom suck on the 215th drop and the colour was off-white now.

*Palmolive- The water became thick very quick, also the colour. The water was very orange on its 133rd drop. The bubbles were big compared to dove.

*Ivory for the first 11 drops the button floated. The waters colour changed rapidly and became thik. For the 9th drop the button only floated for 2 seconds. It smelt more like Ivory. the button sunk after 3 tries on the 31th drop.

*Sunlight

Boiled

*Dove The button still remaind floating after numerous amounts of drops. There were more small bubbles forming at the surface of the water along the cup. The water began to turn whitish and started to smell like dove. The results of each drop were the same, until the 155th drop where the button sank after 3 tries.

*Palmolive For the first nine drops the button floated. After the tenth drop the button remained floating. The button floated until the other detergents. The button finally sank on the 142nd drop. The water was very orangey.

*Ivory The experiment went very quickly. the watercolour didn't change a lot. The water formed quickly. All the results were the same until the 29th drop where the button sank. We tested it out 3 times to make sure and it sank.

*Sunlight The colour of the water changed gradually. The level of the water started to rinse just a little. Small bubbles formed at the water's surface right after each stirring. The water smelt like the detergent. The button sank at 135 drops.

Tap

*Dove The button was already forming bubbles on the 3rd drop. The water turns whitish very quickly. For the 86th drop the button floated for 3 seconds. The button finally sunk at 155 drops. The water was very whitish now.

*Palmolive At the 5th drop the water starts to look like spit. The bubbles forming were very big. The water becomes think on the 15th drop and is light yellow. We noticed the button started to float underneath the surface of the water. The button sunk 3 times at the 42nd drop.

*Ivory For the first 14 drops the button floated. Bubbles were forming quickly after each stir. It floated for 2 seconds on the 15th drop. The colour didn't change significantly.

*Sunlight For the 20th drop the water begun to become orange like the detergents colour. Bubbles formed when we reached to the 5th drop. the button sunk at 83 drops. Sunlight was thick compared to the other detergents.

Home