Question

If someone told you : " Since exothermic processes are favored and the sign of enthalpy change tells us whether or not a process is endothermic or exothermic, then the sign of enthalpy change of a solution tells us whether or not a solution will form " ... How would you explain to him that this conclusion is not correct ??

Answer 1

Answer:

The conclusion is not correct.

Explanation:

Even some reactions are exothermic, they are not favoured ,may be because their activation energy is higher. Even though, some reactions are endothermic, they do take place .

In simpler words, only heat of enthalpy is not the only factor that determine the spontaneity of a reaction.

• There is an another term called entropy which also determine spontaneity.

• The collective term is ∆G = ∆H - T∆S, if it is negative, the reaction is spontaneous.

Answer 2

Answer:

Explanation:

Yes it is correct

• Take the example of bond formation reaction

it will be always exothermic as heat will be liberated to the surrounding in order to get the stability

• In the case of bond breakage,

i will be always endothermic as the energy is taken by the molecules from the surrounding to get the desired compound