H2S is a gas and water is liquid at room temperature. Because, In water there is strong hydrogen bonding, and the molecules get extensively associated by weak electrostatic forces. So, water exists as a liquid at room temperature with a high boiling point. Whereas, Sulphur is less electronegative than oxygen, and the S-H bond is much less polar than the O-H bond. Hence, there is no hydrogen bonding in hydrogen sulphide, and it exists as a gas.