Reaction with water
Magnesium virtually has no reaction with cold water.
It reacts slowly with hot water to give hydrogen gas and white magnesium hydroxide, which is only slightly soluble in water.
Magnesium + water —> magnesium hydroxide solution + hydrogen
Mg(s) + 2H2O(l) —> Mg(OH)2(s) + H2(g)
Magnesium can react vigorously with steam to give an intense white light. Hydrogen gas and a white solid of magnesium oxide
Hydrogen gas is given out in the reaction. The resulting alkaline solution will
turn red litmus blue because of the magnesium hydroxide formed.
Magnesium + steam —> magnesium oxide + hydrogen
Mg(s) + H2O (g) —> MgO(s) + H2(g)
Reaction with oxygen
Strong heating is required to make magnesium burn in oxygen.
Once the reaction starts, it gives an intense brilliant white flame to produce a white powder of magnesium oxide.
magnesium + oxygen —> magnesium oxide
2Mg(s) + O2(g) —> 2MgO(s)
Reaction with dilute acids
Magnesium reacts with dilute hydrochloric acid to give magnesium chloride and hydrogen gas.
magnesium + hydrochloric acid —> magnesium chloride + hydrogen
Mg(s) + 2HCl(aq) —> MgCl2(aq) + H2(g)
Magnesium reacts with dilute sulphuric acid to give magnesium sulphate and hydrogen gas.
magnesium + sulphuric acid —> magnesium sulphate + hydrogen
Mg(s) + H2SO4 (aq) —> MgSO4(aq) + H2(g)
Magnesium reacts with dilute nitric acid to give magnesium nitrate and hydrogen gas.
magnesium + nitric acid —> magnesium nitrate + hydrogen
Mg(s) + 2HNO3(aq) —> Mg(NO3)2(aq) + H2(g)