Question

To test the
the presence of c02 in air​

Answer 1

The most effective way to test for CO2 is to bubble the gas through "limewater", a diluted solution of calcium hydroxide (slaked lime). When you bubble carbon dioxide through the solution, it forms a solid precipitate of calcium carbonate – chalk or limestone.

Answer 2

CO2 is known by its effervescence - the same bubble formation and fizzing sound which happens whenever you open a coke bottle. the test for it is Limewater test. It turns Limewater milky.