Metals are usually electron donors, that is, they are electropositive. Hydrogen is also an electron donor in Water molecule to Oxygen atom. Metals with more electropositivity can replace Hydrogen from water like Sodium. So such metals replace Hydrogen in dilute acids and form salts.\xa0Example: 2 Na + 2 HCl ==> 2 Na Cl + H2\xa0Non metals can be electron acceptors or electron donors. If they are electron acceptors, then they are electronegative. They may replace Oxygen or Hydroxide or a Halogen. But they do not replace Hydrogen.\xa0Many non-metals are below Hydrogen in the reactivity series. They are weaker than Hydrogen. So they do not displace Hydrogen from dilute acids. So nonmetals do not react with dilute acids.\xa0

Because non-metals accept electrons..so, they are unable to give electrons in the acidic medium to release hydrogen gas..