Pratyush took sulphur powder on a spatula and heated it. He collected the gas evolved by inverting a test tube over it, as shown in figure below.
(a) What will be the action of gas on
(i) dry litmus paper?
(ii) moist litmus paper?
(b) Write a balanced chemical equation for the reaction taking place.
Action of gas on dry litmus paper: The gas evolved from heating sulphur powder will have no effect on dry litmus paper. It will not change the color of the litmus paper.
Action of gas on moist litmus paper: The gas evolved from heating sulphur powder will turn moist litmus paper red. This indicates that the gas is acidic in nature.
Balanced chemical equation for the reaction: The balanced chemical equation for the reaction of sulphur powder with heat can be written as: S(s) + O2(g) → SO2(g)
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