Easy MCQ +4 / -1 PYQ · JEE Mains 2020

Lattice enthalpy and enthalpy of solution of NaCl are 788 kJ mol–1, and 4 kJ mol–1, respectively.
The hydration enthalpy of NaCl is :

  1. A –780 kJ mol<sup>–1</sup>
  2. B –784 kJ mol<sup>–1</sup> Correct answer
  3. C 780 kJ mol<sup>–1</sup>
  4. D 784 kJ mol<sup>–1</sup>

Solution

$\Delta$H<sub>sol</sub> = Lattice enthalpy + $\Delta$H<sub>hyd</sub> <br><br>$\Rightarrow$ 4 = 788 + $\Delta$H<sub>hyd</sub> <br><br>$\Rightarrow$ $\Delta$H<sub>hyd</sub> = –784 kJ mol<sup>–1</sup>

About this question

Subject: Chemistry · Chapter: Thermodynamics · Topic: Zeroth and First Law

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