Question

Be and Mg do not react with water. This is because of?

Answer 1

• Magnesium and Beryllium both are alkaline earth metals.
• Beryllium has an atomic number of 4 and Magnesium has an atomic number of 12.
• Due to the small size and high ionization energy of Beryllium it is unable to form bonds with the water molecules.
• Also due to the formation of a thin layer of Beryllium oxide$\left(\mathrm{BeO}\right)$ over the Beryllium metal, it prevents it from reacting with water at lower temperatures.
• As a result Beryllium does not react with water.
• Magnesium when reacts with water form Magnesium hydroxide$\left(\mathrm{Mg}{\left(\mathrm{OH}\right)}_2\right)$ which is insoluble in water and thus creates a barrier to the magnesium preventing further reaction.
• Thus Magnesium also does not reacts with water.