Question

If one litre of air is passed repeatedly on hot copper and hot magnesium till no further decrease in volume takes place, the volume of residual gas would be about ______.

Options

• 200 mL

• 100 mL

• 10 mL

• zero

Answer 1

If one litre of air is passed repeatedly on hot copper and hot magnesium till no further decrease in volume takes place, the volume of residual gas would be about 10 mL.

Explanation:

Hot copper removes oxygen, and hot magnesium removes nitrogen from the air. The remaining air is mainly noble gases, which make up about 1% of air. Thus, the residual volume from 1 litre of air is about 10 mL.