question_answer

\[{{H}_{2}}O\]is a liquid while \[{{H}_{2}}S\] is a gas at room temperature. Explain.

Answer:

                \[H-O\]bond is more polar than \[H-S\] bond because of greater electro negativity difference in the bonding atoms. As a result, \[{{H}_{2}}O\]molecules are involved in the intermolecular hydrogen bonding and get associated to be liquid at room temperature. Since intermolecular hydrogen bonding is negligible in the molecules of \[{{H}_{2}}S,\] they do not get associated and remain m the gaseous state at room temperature. For more details, consult text part (Section 7.16).