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COMEDK2016ChemistryThermodynamics (C)

The enthalpy of the reaction, H ₂(g)+1 / 2 O ₂(g) H ₂ O (g) is H₁ and that of H ₂(g)+1 / 2 O ₂(g) H ₂ O (l) is H ₂ . Then

Options

  1. AH₁> H₂
  2. BH₁= H₂
  3. CH₁ < H₂
  4. DH₁+ H₂=0

Correct answer

C. H₁ < H₂

Step-by-step solution

H ₂(g)+ 1 2 O ₂(g) H ₂ O (g) ; H ₁=+ ve H ₂ O (g) H ₂ O (l) ; H ₃=+ ve H ₂(g)+ 1 2 O ₂(g) H ₂ O (l) ; H₂= H₁+ H₃ H₂> H₁

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