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.
$(b)$ ${{S}_{(s)}}\,+\,{{O}_{2(g)}}\,\to \,\underset{\text{ Sulphur dioxide }}{\mathop{S{{O}_{2(g)}}}}\,$
$S{{O}_{2(g)}}\,+\,{{H}_{2}}{{O}_{(l)}}\,\to \,\underset{\text{ Sulphurous acid }}{\mathop{{{H}_{2}}S{{O}_{3(aq)}}}}\,$
Which gas is produced when dilute hydrochloric acid is added to a reactive metal? Write the chemical reaction when iron reacts with dilute $H_2SO_4$.
You are given a hammer, a battery, a bulb, wires and a switch.
$(a)$ How could you use them to distinguish between samples of metals and non-metals ?
$(b)$ Assess the usefulness of these tests in distinguishing between metals and non-metals.
Give reasons : Platinum, gold and silver are used to make jewellery.
An element reacts with oxygen to give a compound with a high melting point. This compound is also soluble in water. The element is likely to be
Which of the following pairs will give displacement reactions ?