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COMEDK2013ChemistryThermodynamics (C)

The enthalpies of formation of Al ₂ O ₃ and Cr ₂ O ₃ are -1596 ~kJ and -1134 ~kJ respectively. H for the reaction, 2 Al + Cr ₂ O ₃ 2 Cr + Al ₂ O ₃ is

Options

  1. A-2730 ~kJ
  2. B-462 ~kJ
  3. C-1365 ~kJ
  4. D+2730 ~kJ

Correct answer

B. -462 ~kJ

Step-by-step solution

H_ Reaction = ( H_ f )_ Product - H_ f )_ Reactant =-1596-(-1134)=-462 ~kJ

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