Question

murli took sulphur powder on a spatula and heated it. he collected tha gas evolved by inverting a test tube over it .
1. what will be the action of gas on 
2. write the balanced chemical equation for the reaction taking place

Answer 1

1.  When  sulphur burns it first turns into blood red liquid form and then into a gas emitting a blue flame. It is best visible in dark. The gas formed is Sulphur dioxide. SO2 has a peculiar suffocating odor.  If all the air is consumed in burning and no fresh air goes in to the tube, burning will stop. Otherwise, all sulphur will burn.

2.                    heat
        S + O2      =>      SO2