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MHT CET2010ChemistryThermodynamics (C)

The heat of formation of water is 260 ~kJ . How much H ₂ O is decomposed by 130 ~kJ of heat ?

Options

  1. A0.25 ~mol
  2. B1 ~mol
  3. C0.5 ~mol
  4. D2 ~mol

Correct answer

C. 0.5 ~mol

Step-by-step solution

The reaction for the formation of water is as H ₂+ 1 2 O ₂ H ₂ O ; H=260 ~kJ (i) On reversing Eq. (i), we get 1 H ₂ O H ₂+ 1 2 O ₂ H=-260 ~kJ By 260 ~kJ heat water decomposed =1 ~mol 130 k _ I I hont will decomposo water = 1 130 260 =0.5 ~mol

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