Question

A solution of substance ‘X’ is used to show the presence of CO2 in exhaled air. Identify
the substance X. How does the solution of substance ‘X’ indicate the presence of CO2? Write
the chemical reaction involved in the above reaction

Answer 1

Answer:

For testing carbon dioxide, CALCIUM HYDROXIDE is used which is generally called as Lime Water. ... 1) Substance x is obtained by adding water and calcium oxide. 2) X can be obtained by reaction of calcium with water.

Answer 2

The substance X is limewater or filtered slaked lime solution- Ca(OH)2 soln.

Limewater turns milky by absorbing carbon dioxide forming insoluble calcium carbonate as a white precipitate.

Ca(OH)2 + CO2-------->CaCO3 + H2O