Reference state for entropy definition of entropy change 4s=&-9-(9 int Arbitrarily choosing reference state x,then at any state y, replace state 1 replace state 2 Because of cancel" s=s+(9 int rev Only for constant composition applications, for chemical reactions,use absolute values (3d law) (Chap.15) 上游气通大粤 Wednesday,April 12,2017 3 SHANGHAI JIAO TONG UNIVERSITYWednesday, April 12, 2017 3 Reference state for entropy definition of entropy change Arbitrarily choosing reference state x, then at any state y, replace state 1 replace state 2 Only for constant composition applications, for chemical reactions, use absolute values (3rd law) (Chap. 15) Because of “cancel