Give a statement of Hess's law.

Solutions

Expert Solution

Hess law states that if a reaction takes place in more than one strp, then enthalpy of this reaction is sum of enthalpy of individual steps.

For example:

Suppose the required reaction is:

C + 2H2O —> CO2 + 2 H2

Its enthalpy can be calculated by taking sum of enthalpy of below 2 reactions

C + O2 —> CO2

2 H2O —> 2 H2 + O2

queen_honey_blossom answered 2 years ago

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