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MHT CET20239 May 2023Morning ShiftChemistryThermodynamics (C)Actual

Which among the following reactions exhibits H = U ?

Options

  1. AH _ 2( ~g ) + Br _ 2( ~g ) 2 HBr _ ( g )
  2. B2 CO _ ( g ) + O _ 2( ~g ) 2 CO _ 2( ~g )
  3. CPCl _ 5( ~g ) PCl _ 3( ~g ) + Cl _ 2( ~g )
  4. DC _ ( s ) +2 H ₂ O _ ( g ) 2 H _ 2( ~g ) + CO _ 2( ~g )

Correct answer

A. H _ 2( ~g ) + Br _ 2( ~g ) 2 HBr _ ( g )

Step-by-step solution

When n _ g =0, H = U . For reaction (A), n _ g =0 .

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