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JEE Advanced2019ChemistryThermodynamics (C)Actual

Choose the reaction(s) from the following options, for which the standard enthalpy of reaction is equal to the standard enthalpy of formation.

Options

  1. A3 2 O 2 g → O 3 g
  2. B1 8 S 8 s + O 2 g → S O 2 g
  3. C2 H 2 g + O 2 g → 2 H 2 O l
  4. D2 C g + 3 H 2 g → C 2 H 6 g

Correct answer

A. 3 2 O 2 g → O 3 g

Step-by-step solution

Standard enthalpy formation of a compound is the amount of enthalpy charge involved when one mole of a compound is formed from the reactants present in their elementary form,

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