2. Solved Papers
  3. CMC Medical

CMC Medical CMC-Medical VELLORE Solved Paper-2015

  • question_answer
    18 g of ice is converted into water at \[0{}^\circ C\]and 1 atm. The entropies of \[{{H}_{2}}O\,(s)\] and \[{{H}_{2}}O\,(l)\] are 38.2 and\[60\,J\text{/}mol\text{ }K\]respectively. The enthalpy change for this conversion is

    A)  595.14 J/mol                     

    B)  - 5951.4 J/mol

    C)  5951.4 J/mol                     

    D)  - 595.14 J/mol

    E)  21.8 J/mol

    Correct Answer: C

    Solution :

                    At equilibrium \[\Delta H=T\cdot \Delta \,S\] \[{{H}_{2}}O(s)\xrightarrow{{}}{{H}_{2}}O(l)\] \[\Delta S={{S}_{{{H}_{2}}O(l)}}-{{S}_{{{H}_{2}}O(s)}}\] \[=(60-38.2)\,J\text{/}mol\text{-}K=21.8\,J\text{/}mol\text{-}K\] \[\Delta H=273\times (21.8)=5951.4\,J\text{/}mol\]


You need to login to perform this action.
You will be redirected in 3 sec spinner