In a molecule of water, there are two shared pairs of electrons between one oxygen atom and two hydrogen atoms.

Chlorine forms a single covalent bond in Cl₂ by sharing a pair of electrons between two chlorine atoms, each contributing one electron. This bond satisfies the octet rule for both chlorine atoms, allowing them to achieve stability.

There are seven electrons present in the valence shell of a chlorine atom.

Chlorine has a valency of 1, as it requires one more electron to complete its octet and achieve stability.

The electronic configuration of chlorine (atomic number 17) is 1s² 2s² 2p⁶ 3s² 3p⁵.