The two thermodynamic quantities, which affect the spontaneity of a reaction, are enthalpy (H) and entropy (S). The free energy of a substance, like its entahlpy or entropy is a characteristic property of the substance. In any reaction, the change in free energy,
DG = GProducts – GReactants
For a reaction carried out at constant temperature and pressure,
(i) If DG is negative, the forward reaction is spontaneous
(ii) If DG is positive, the forward reaction is non-spontaneous. Instead, the reverse reaction will be spontaneous.
(iii) If DG is zero, the system is at equilibrium. There is no tendency for the net reaction to take place in either direction.
Relation between DG, DH and DS
DG is made up of two terms; an energy term and an entropy term.
DG = DH – TDS
where T is the temperature in Kelvin. This equation tells us that the driving force for a reaction, DG, represents two quantities. One of these is the enthalpy change due to the making and breaking of bonds, DH. The other is the product of the change in randomness, DS times the absolute temperature T.
7.18 Standard Free Energy Change (DG°) and Eq. Constant (Keq)DG° = – 2.303 RT log Keq
We are the leading online assignment help provider. Find answers to all of your doubts regarding the Free Energy Change in chemistry. We at assignmenthelp.net provide homework, assignment help to the school, college or university level students. Our expert online tutors are available to help you in Free Energy Change. Our service is focused on: time delivery, superior quality, creativity and originality.
Chemistry Assignment Help | Chemistry tutor | Science tutor | Chemistry help | Chemistry homework help | Organic chemistry help | Help with chemistry | Online chemistry help | Free chemistry help | High school chemistry help | College chemistry help | General chemistry help | AP chemistry help | Help in chemistry | Help with chemistry homework | Chemistry experiments | homework help | Homework assignment help | Online tutoring services | Online Tutoring