Tuesday, 19 May 2009

The underwater drop


1. A small container and a big glass.
2. Oil
3. Water
4. Alcohol
5. Glue and coin.
6. A spoon.

If the container is made of plastic, we stick a coin at its base in order to get more stability and avoid floating.

We fill the half a container with oil.
We put it at the bottom of the glass.
We pour the alcohol necessary to cover the container very carefully.

Then, we add water little by little with a spoon (it must slip from the wall of the glass).
Small container's surface filled with oil will adopt a convex shape until the water you add is enough. Then, the oil will separate from this container and it will have a spherical form that will remain just in the middle inside the oil and water mixture.

First, we must know the densities of the liquids we use in the experiment.
- water (1g/ml)
- oil (0'92 g/ml)
- Alcohol (0'75 g/ml)

The oil floats in the water because it's less dense than water, but it sinks into alcohol because it's denser than it. In conclusion, you can prepare a mixture with alcohol and water because inside it, oil won’t float or sink.

by Ana, Marta and Belén


Manuel Díaz Escalera said...

The experiment is well explained. Congratulations

ayahidalgo@hotmail.com said...

Your experiment is well done, quite original. You have explained it to be understood without any problem. I´m an English teacher and I consider it a good way to imrpove your English too. Go on, it´s a magnificent experience!

Ana, Marta and Belén said...

Thank you very much!! =)

Anonymous said...

Belen, ana and marta said..
it isnt sink and float...jajajaja. its a joke.=)

Camino said...

Me ha encantado.

Anonymous said...

it's a wonderful experiment!! we love the way people say they understood everything!
You're so good girls! a kiss for your perfect english.