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MHT CET202120 Sep 2021Morning ShiftChemistryThermodynamics (C)Actual

Calculate heat of formation of HCl gas from following reaction. H _ 2( ~g ) + Cl _ 2( ~g ) 2 HCl _ ( g ) ; H =-194 ~kJ

Options

  1. A-143 ~kJ ~mol ⁻¹
  2. B-286 ~kJ ~mol ⁻¹
  3. C-92 ~kJ ~mol ⁻¹
  4. D-97 ~kJ ~mol ⁻¹

Correct answer

D. -97 ~kJ ~mol ⁻¹

Step-by-step solution

aligned & H _ 2( ~g ) + Cl _ 2( ~g ) 2 HCl _ ( g ) , H =-194 ~kJ & H _ reaction =2 H _ f ( HCl ) - H _ f ( H ₂ ) - H _ f ( Cl ₂ ) & -194=2 H _ f ( HCl ) - O - O & H _ f ( HCl ) =-194 / 2 & =-97 ~kJ / mol aligned

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