2. Questions Bank
  3. NEET
  4. Chemistry
  5. Thermodynamics / रासायनिक उष्मागतिकी

NEET Chemistry Thermodynamics / रासायनिक उष्मागतिकी Question Bank Self Evaluation Test - Thermodynamics

  • question_answer
    What is the normal boiling point of mercury? Given: \[\Delta H_{f}^{{}^\circ }\left( Hg,l \right)=0;\text{ }S{}^\circ \left( Hg,l \right)=77.4\text{ }J/K\]-mol \[\Delta H_{f}^{{}^\circ }\left( Hg,g \right)=60.8\text{ }kJ/mol;\text{ }S{}^\circ \left( Hg,g \right)=174.4J/K-mol\]

    A) 624.8 K            

    B) 626.8 K

    C) 636.8 K            

    D) None of these

    Correct Answer: B

    Solution :

    [b] \[Hg(l)\rightleftharpoons H(g),\] \[{{\Delta }_{R}}{{S}^{{}^\circ }}=174.4-77.4=97J/K-mol\] \[\therefore \text{ }\Delta {{G}^{{}^\circ }}=\Delta {{H}^{{}^\circ }}-T\Delta {{S}^{{}^\circ }}=0\] \[T=\frac{\Delta {{H}^{{}^\circ }}}{\Delta {{S}^{{}^\circ }}}\] \[=\frac{60.8\times 1000}{97}=626.8K\]


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