Materials Required
  • A bottle with a narrow neck
  • Vinegar
  • Baking soda
  • Funnel or straw
  • Water
  • Balloon

How to do it

  • Pour about an inch of liquid  half of vinegar, half of water into the bottle.
  • Use the funnel to fill the balloon half full of baking soda.
  • Stretch the open end of the balloon over the neck of the bottle. Make sure it is fit in the mouth tightly.
  • Take care that the baking soda from the balloon should not spill into the bottle.
  • |Now, hold onto the balloon at the bottle neck, and pick up the heavy part of the balloon so that all the baking soda falls into the vinegar at the bottom of the bottle.
  • Ask the child to observe what happens. The balloon should start inflating.

Explanation

When the baking soda comes in contact with the vinegar, there takes a chemical reaction and the carbon di oxide gas is released. The gas released causes the increase in the pressure inside the bottle and makes the balloon to expand.