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AP EAMCET202420 May 2024Morning ShiftChemistryThermodynamics (C)Actual

Observe the following reaction 2 ~A ₂( ~g )+ B ₂( ~g ) T ( K ) 2 ~A ₂ ~B ( ~g )+600 ~kJ The standard enthalpy of formation ( _ f H ^ ) of A ₂ ~B ( ~g ) is

Options

  1. A600 ~kJ ~mol ⁻¹
  2. B300 ~kJ ~mol ⁻¹
  3. C-300 ~kJ ~mol ⁻¹
  4. DMissing

Correct answer

C. -300 ~kJ ~mol ⁻¹

Step-by-step solution

Given reaction -2 ~A ₂+ B ₂ 2 ~A ₂ ~B +600 ~kJ By this equation indicates that the formation of 2 moles of A ₂ ~B releases 600 kJ energy. H _ f ^ ( A ₂ ~B )= Total enthalpy change Number of moles of A ₂ ~B H _ f ^ ( A ₂ ~B )= 600 ~kJ 2 =300 ~kJ / mol Since reaction ^2 releases energy (Exothermic). The enthalpy of formation is negative. H_f^ =-300 ~kJ / mol

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