Why is `H_(2)O` a liquid and `H_(2)S` a gas?

Explanation

`H_(2)O` undergoes extensive intermolecular H -bonding as O is more electronegative than S . Thus `H_(2)O` exists as an associated molecule in which each O -atom is tetrahedrally surrounded by four water molecules. To break these H -bonds, a large amount of energy is required. Therefore, `H_(2)O` is a liquid at room temperature.
However, in `H_(2)S`, as there is no H-bonding, the molecules are discrete and are held by weak van der Waals forces of attraction. To break these forces a small amount of energy is required. Therefore, `H_(2)S` is a gas at room temperature.