Write the names and symbols of the constituents present in the following alloys:
$(a)$ Brass
$(b)$ Bronze
$(c)$ Solder

Solder is an alloy of lead and tin. It has a:

Give reasons for the following:
$(i)$ Metals conduct electricity.
$(ii)$ Non-metals in general do not displace hydrogen from dilute acids.
$(iii)$ Aluminium easily combines with oxygen but still it can be used for making kitchen utensils.

Why do ionic compounds not conduct electricity in the solid state?

Explain the following:
$(a)$ $NaCl$ is not a conductor of electricity in solid state,whereas it does conduct electricity in aqueous solution as well as in molten state.
$(b)$ Iron articles are galvanised.
$(c)$ Metals like $Na, K, Ca$ and $Mg$ are never found in their free state in nature.

Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of: