Question

With the help of an experiment prove that exhaled air contains carbon dioxide.

Answer 1

Aim: To prove that exhaled air contains carbon dioxide.

Materials Required: tape, two beakers, limewater, cardboard and straw

Procedure:

1. Take two beakers A and B containing equal volumes of lime water.
2. Cover both beakers with cardboard using tape and make holes in them for straw.
3. Blow air in beaker B with the help of a straw while leaving the beaker A undisturbed.

Observation:

1. Lime Water in beaker B first turns milky.
2. Lime Water in beaker A does not turn milky

Inference:

1. When air is blown in beaker B, exhaled air contains carbon dioxide and hence, the lime water in beaker B turns milky as soon as we blow air into it.
2. Lime water in beaker A remains the same as no carbon dioxide has entered it.