Question

An element A has four electrons in the outermost shell of its atom and combines with another element B having seven electrons in the outermost shell. The compound formed does not conduct electricity. Give any two properties of this compound.

Answer 1

Formation of covalent compound: Element A has 4 electrons in the outermost shell of its atom, so neither the gain of an electron nor the loss of an electron is helpful to it in achieving the stable configuration. Hence, Element A shares electrons with 4 atoms of element B as each element of B needs sharing of only 1 electron. Hence, elements A and B form a covalent compound, AB₄.

Properties of covalent compound AB₄:

1. Covalent compounds have low melting and boiling point.
2. Covalent compounds are insoluble in water.