# Magnesium is added to a solution to check for acidity. If the solution is an acid, what will happen?

Jul 1, 2016

Hydronium ion, ${H}_{3} {O}^{+}$ or ${H}^{+}$, will oxidize magnesium metal to give dihydrogen.

#### Explanation:

$M g \left(s\right) + 2 {H}_{3} {O}^{+} \rightarrow M {g}^{2 +} + {H}_{2} \left(g\right) \uparrow + 2 {H}_{2} O \left(l\right)$

Jul 1, 2016

The acid and magnesium will together form a salt and ${H}_{2} \left(g\right)$.

#### Explanation:

Magnesium is an active metal, which means that a salt and ${H}_{2}$ gas will be formed as a result of a chemical reaction with any acid. For example, if there is $H C l$ (hydrochloric acid) in the solution, they will together form $M g C {l}_{2}$ and ${H}_{2}$.
Some other examples of chemical equations which include $M g$ and an acid:

$2 M g + {H}_{2} S {O}_{4} \to M {g}_{2} S {O}_{4} + {H}_{2}$
$M g + 2 H N {O}_{3} \to M g {\left(N {O}_{3}\right)}_{2} + {H}_{2}$
$M g + 2 {H}_{3} P {O}_{4} = M g {\left(P {O}_{4}\right)}_{2} + 3 {H}_{2}$