Question

give the characteristic test for the following gases CO2 ...... SO2 and H2

Answer 1

for CO2
when carbon dioxide is passed through lime water it turns limewater milky .
for H2
when burning candle is brought towards H2 it burns with pop sound
for SO2
when it is passed through water it make acid like acid rain

Answer 2

CO2 test is pass through lime water, lime water turns milky.

SO2 test i don't know.

h2 test is bring burning matchstick near burning candle,  it burns with pop sound.