An element of group 2 forms covalent oxide which is amphoteric in nature and dissolves in water to give an amphoteric hydroxide. Identify the element and write chemical reactions of the hydroxide of the element with an alkali and an acid.

Explanation

The alkaline earth metals burn in oxygen to form monoxide `MO.BeO` is essentially covalent in nature, other being ionic in nature. `BeO` is amphoteric while other oxides are basic in nature and react with water to form sparingly soluble hydroxides. `BeO` dissolves both in acid and alkalis to give salt and is amphoteric.
`BeO +H_(2)O rarr underset("Beryllium hydroxide")(Be(OH)_(2))`
`Be(OH)_(2)` is an amphoteric hydroxide, dissolving in both acids and alkalies. with alkalies it dissolve to form the tetrahydroxidoberyllate `(Z^(-))` anion with sodium hydroxide solution.
`2NaOH(aq)+Be(OH)_(2)(s)rarr underset("Sodium tetra hydroxidoberyllate")(Na_(2)Be(OH)_(4)(aq))`
With acids, it forms beryllium salts.
`Be(OH)_(2)+underset("Sulphuric acid")(H_(2)SO_(4))rarr underset("Beryllium sulphate")(BeSO_(4))+2H_(2)O`