For the reaction, \(2Cl(g)→Cl_2(g)\), what are the signs of \(∆H\) and \(∆S\) ?
Solution and Explanation
\(∆H \)and \(∆S\) are negative.
The given reaction represents the formation of chlorine molecule from chlorine atoms. Here, bond formation is taking place. Therefore, energy is being released. Hence, \(∆H\) is negative.
Also, two moles of atoms have more randomness than one mole of a molecule. Since spontaneity is decreased, \(∆S\) is negative for the given reaction.
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Concepts Used:
Gibbs Free Energy
The energy associated with a chemical reaction that can be used to do work.It is the sum of its enthalpy plus the product of the temperature and the entropy (S) of the system.
The Gibbs free energy is the maximum amount of non-expansion work that can be extracted from a thermodynamically closed system. In completely reversible process maximum enthalpy can be obtained.
ΔG=ΔH−TΔS
The Conditions of Equilibrium
If both it’s intensive properties and extensive properties are constant then thermodynamic system is in equilibrium. Extensive properties imply the U, G, A.
