Question

Do all metals react with bases to give H2 or all metals react to give H2?

Answer 1

Depends on metal

Most metals will not react with bases. But others, called amphoteric metals, may form salts with them.

Example :(aluminium, tin, lead, zinc and antimony )
Aluminium will form a salt with acids, like:
Al+3HCl→AlCl3+1.5H2Al+3HCl→AlCl3+1.5H2 (aluminium chloride)
Or Al+3H+→Al3++1.5H2Al+3H+→Al3++1.5H2

But also with a base, like:
Al+3NaOH→Na3AlO3+1.5H2Al+3NaOH→Na3AlO3+1.5H2 (sodium aluminate)
Or Al+3OH−→AlO3−3+1.5H2