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KCET2009ChemistryThermodynamics (C)

The enthalpy of formation of NH ₃ is -46 ~kJ ~mol ⁻¹ . The enthalpy change for the reaction 2 NH ₃( ~g ) N ₂( ~g )+3 H ₂( ~g ) is

Options

  1. A+184 ~kJ
  2. B+23 ~kJ
  3. C+92 ~kJ
  4. D+46 ~kJ

Correct answer

C. +92 ~kJ

Step-by-step solution

2 NH ₃(g) N ₂(g)+3 H ₂(g) H _ r =- (2 . enthalpy of formation of . NH ₃ ) =-(2 -46)=92 ~kJ

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