You will need:
- water
- vegetable oil/olive oil
- grounded coffee
- salt
- tall glass or jar
Method:
1.
Fill the glass with 2/3 of
water.
2.
Add 2-3 cm of vegetable
oil.
3.
Sprinkle a teaspoon of
coffee on the top of the oil.
4.
Take a pinch or two of
salt and sprinkle it on top.
5.
Observe what happens.
How does it work?
Research: density
