Question

How to test the CO2 gas liberated

Answer 1

by passing it to lime water

Answer 2

CO2 gas has the following test :

⇒ CO2 turns a lime water milky

⇒ CO2 has no effect on acidified KMnO4 paper

⇒ SO2 also turns lime water milky

⇒ But SO2 has certain effects on KMnO4 paper

⇒ CO2 hence can be detected by passing the gas through acidified KMnO4 paper

Hope it helps

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