Question

Suppose you have to determine the percentage of carbon dioxide in a sample of gas available in a container. Which among the following is the best absorbing material for carbon dioxide?

• A. Heated copper oxide
• B. Cold, solid calcium chloride
• C. Cold, solid calcium hydroxide
• D. Heated charcoal

Answer 1

The correct option is C

Cold, solid calcium hydroxide

$C{O}_2$ is an acidic oxide and thus more effectively absorbed by an alkali. Therefore cold solid calcium hydroxide is the best absorbing material for the carbon dioxide.