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Enthalpy, entropy and free energy of for...

Enthalpy, entropy and free energy of formation of elementary substances in the standard state are taken as zero.

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To understand why the enthalpy, entropy, and free energy of formation of elementary substances in their standard state are taken as zero, we can break it down step by step. ### Step-by-Step Solution: 1. **Definition of Standard State**: - The standard state of a substance is defined as its most stable form at 1 bar (or 1 atm) pressure and a specified temperature, usually 25°C (298 K). For example, the standard state of oxygen is O₂ gas, and for carbon, it is graphite. 2. **Enthalpy of Formation**: ...
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