Question

What reaction yields hydrogen gas from magnesium metal and water?

Answer 1

A redox reaction..........

Explanation:

The metal is oxidized to `Mg^(2+)`:

`Mg(s) rarr Mg^(2+) + 2e^(-)`

Steam is reduced to dihydrogen gas:

`H_2O + 2e^(-) rarr O^(2-) + H_2(g)`

Adds them together:

`Mg(s) + H_2O(g) rarr MgO(s) + H_2(g)`