Blowing Up A Balloon with Lemon Juice

Science Concept: Mixing a carbonate base with an acid results I carbon dioxide.

Materials & Pre-Demo Preparation:

Lemon juice

1 Balloon

Empty soda bottle

30 mL water

1 teaspoon baking soda (5 g)

Funnel

lighter

Directions:

1. Place the balloon around stem of the funnel.
2. Put baking soda into balloon.
3. Pour lemon juice and water into bottle.
4. Place end of balloon around neck of bottle.
5. Let baking soda fall into bottle and observe

Variation: The carbon dioxide balloon can be ignited to compare the property of carbon dioxide gas with that of hydrogen gas. The carbon dioxide does not ignite and does not therefore make a loud bang as compared to the hydrogen balloon.

Introduction & Commentary: I hate blowing up balloons, so I have come up with a new way of inflating a balloon without my having to blow into it. Watch and see!

Explanation: The combination of an acid and base causes a chemical reaction. The product is a gas, bubbles that are carbon dioxide. The carbon dioxide gas is trapped in the balloon and it inflates. The carbon dioxide gas molecules created a pressure by colliding with the sides of the balloon. As more carbon dioxide is produced, the more collisions cause more pressure, the more pressure that is created causes the balloon to inflate.

When an acid and a bicarbonate mix, they cause a chemical reaction, and in a chemical reaction there is always a product that has formed. In this case, it is a gas called carbon dioxide. Does anyone know what carbon dioxide is? It is the gas we breathe out, and the gas that plants breathe in.

Safety Precautions: The chemicals and other equipment are non-toxic. Use normal safety precautions.

Waste Disposal: Throw away the balloon remains in the garbage. The bottle can be washed with tap water and flushed down the drain.

Reference: Mandell, M. Simple Science Experiments with Everyday Materials. pp.53.