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Write an application of Hess’s law. - Chemistry

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Write an application of Hess’s law.

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Solution 1

The Hess's law has been useful to calculate the enthalpy changes for the reactions with their enthalpies being not known experimentally.

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Solution 2

  1. It helps in calculating the enthalpies of formation of those compounds which cannot be determined experimentally.
  2. It helps in determining the enthalpy of allotropic transformation like C(graphite)→C(diamond)
  3. It helps in calculating the enthalpy of hydration.
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Thermochemistry
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Chapter 4: Chemical Thermodynamics - Long answer questions

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