Write down the equation for the Gibbs Free Energy change of a reaction. Hence explain why, for a spontaneous endothermic reaction, there must be an increase in the total entropy.

Gibbs Free Energy change: (delta)G = (delta)H - T(delta)S For a spontaneous chemical reaction, (delta)G must be negative. An endothermic reaction has a positive (delta)H value therefore, in order for the reaction to be spontaneous, the T(delta)S term must be positive. Since T is in units of K, it cannot be negative, hence (delta)S can only be positive to have an overall positive T(delta)S term. Since (delta)S is positive, this implies an increase in entropy therefore the entropy must increase for the reaction to be spontaneous. 

Answered by James C. Chemistry tutor

2866 Views

See similar Chemistry A Level tutors

Related Chemistry A Level answers

All answers ▸

What are isotopes and how do they differ from each other?


10cm^3 of 1M NaOH solution is mixed with 15cm^3 of 0.5M HCl, what is the resulting pH of the solution?


What is a mole?


What is a chiral carbon and optical isomerism?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences