What’s the effect of gravity on weak surface? Find out in this experiment.
Things Required:
Rubbing alcohol
1 small baby food jar
1 straw
Red or blue food colouring
Clay, a piece the size of a marble
Directions:
Press the clay against the inside of the bottom of the jar. Fill the jar one-half full with alcohol.
Add three or four drops of food colouring to the alcohol and stir. Slowly lower the straw into the coloured alcohol. Push the bottom end of the straw into the clay. The straw can now stand in a vertical position. Quickly turn the jar upside down over a sink.
Turn the jar right side up and set it on a table. Observe the liquid level inside the straw.
This Is What Happens:
The coloured alcohol flows out of the jar and out of the straw.
Science Behind It:
The attraction between the alcohol molecules is not very great, and the pressure of the air in the straw is not enough to hold up the liquid. The downward force of gravity pulls the alcohol out of the straw.
