A metal 'M' reacts with an acid according to the equation.
M + H+→ M3+ + H2.
Which of the following is correct for metal M?
Among the given metals, only aluminium has a stable +3 oxidation state. Aluminium reacts with acid to produce a metal salt and H2 gas. For example: Al reacts with HCl to give AlCl3 and H2 gas.
Reaction:
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