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.
$(a)$ $(i)$ There will be no action on dry litmus paper.
$(ii)$ Since the gas is sulphur dioxide $(SO_2)$, it turns moist blue litmus paper to red because sulphur dioxide reacts with moisture to form sulphurous acid.
$(b)$ ${{S}_{(s)}}\,+\,{{O}_{2(g)}}\,\to \,\underset{\text{ Sulphur dioxide }}{\mathop{S{{O}_{2(g)}}}}\,$
$S{{O}_{2(g)}}\,+\,{{H}_{2}}{{O}_{(l)}}\,\to \,\underset{\text{ Sulphurous acid }}{\mathop{{{H}_{2}}S{{O}_{3(aq)}}}}\,$
Define the following terms.
$(i)$ Mineral $(ii)$ Ore $(iii)$ Gangue
What type of oxides are formed when non-metals combine with oxygen?
Food cans are coated with tin and not with zinc because
Which of the following methods is suitable for preventing an iron frying pan from rusting ?
Give an example of a metal which
$(i)$ is a liquid at room temperature.
$(ii)$ can be easily cut with a knife.
$(iii)$ is the best conductor of heat.
$(iv)$ is a poor conduct of heat.