Give reasons for the following :
Metals replace hydrogen from dilute acids whereas non-metals do not.

Explanation

Metals are electropositive in nature. Their atoms readily lose electrons to form positive ions. The electrons are accepted by `H^(+)` ions of the acid to evolve hydrogen gas. For example,
`Zn(s) rarr Zn^(2+)(aq) + 2e^(-)`
`2H^(+)(aq) + 2e^(-) rarr H_(2)(g)`
Non-metals are electronegative in nature. This means that their atoms can take up electrons and cannot lose them. Therefore, they do not evolve hydrogen on reacting with dilute acids.