For the reaction,

2 Cl(g) Cl2(g), what are the signs of and ?

In the reaction, chlorine molecule is being formed from chlorine atoms. Hence, bond formation takes place, leading to release of energy. As it is exothermic reaction, ∆H is negative (-ve).


In the reaction, 2 moles of atoms having higher randomness combine to form 1 mole of molecules, having lesser randomness.


Therefore, ∆S is negative (-ve ), which is represented as Sproducts – Sreactants.


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