`H_(2)O` has oxygen as the central atom. Oxygen has smaller size and higher electronegativity as compared to sulphur. Therefore, there is extensive hydrogen bonding in `H_(2)O`, which is absent in `H_(2)S`. Molecules of H2S are held together only by weak van der `Waal’`s forces of attraction.
Hence, `H_(2)O` exists as a liquid while `H_(2)S` as a gas.
