Give reasons for the following:
$(i)$ Gold and platinum are used in jewellery.
$(ii)$ Copper cannot displace hydrogen from dilute acids.
$(iii)$ Stainless steel does not rust easily.
$(iv)$ Metals can be given different shapes according to our needs.
$(v)$ Zinc does not give hydrogen gas on reacting with $HNO_3$.

(N/A) $(i)$ Gold and platinum are noble metals that are highly lustrous and resistant to corrosion,making them ideal for jewellery.
$(ii)$ Copper is less reactive than hydrogen in the reactivity series,so it cannot displace hydrogen from dilute acids.
$(iii)$ Stainless steel is an alloy of iron with chromium and nickel,which forms a protective oxide layer that prevents rusting.
$(iv)$ Metals are malleable (can be beaten into sheets) and ductile (can be drawn into wires),allowing them to be shaped as required.
$(v)$ $HNO_3$ is a strong oxidizing agent. When it reacts with metals,it oxidizes the produced hydrogen gas $(H_2)$ into water $(H_2O)$ instead of releasing it.