Question

You are provided with 4 metals ----- Na, Mg, Al and Cu. Using only water as the reactant, how will you identify each of them.​

Answer 1

Na reacts vigorously with water to form NaOH

Mg reacts with hot water only to give magnesium oxide and H2

Al reacts with water to give Al2O3 and hydrogen gas

Cu reacts with hot water to give black cuprous oxide

I hope this helps ( ╹▽╹ )