Question about the rules of thermodynamics

Thread starter samy4408
Start date Apr 6, 2022
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Enthalpy Gibbs free energy Reaction Rules Thermodaynamics Thermodynamics

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To calculate ΔGr ° using ΔGf °, it is essential to adhere to the same principle applied in thermodynamics for ΔHr °. This means that ΔGf ° must be determined for reactions forming 1 mol of compound from pure elements in their most stable form at standard state. The consistency in using standard formation values is crucial for accurate thermodynamic calculations. Therefore, the rules governing ΔHr ° also apply to ΔGr ° calculations. Understanding these principles ensures reliable results in thermodynamic assessments.

Apr 6, 2022

samy4408

Hello , we learned in thermodynamics that to calculate ΔHr °(of the reaction ) using ΔHf °(standard heat of formation ), we have to respect that
ΔHf °=ΔHr ° of a reaction forming 1 mol of compound from pure elements in their most stable form at standard state .
the problem is when we want to calculate ΔGr ° using ΔGf ° is it necessary to respect the rule raised before ?
thanks .

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Apr 6, 2022

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Yes.

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