... khỏc nhau: - Nu P (atm), V(dm3=l) ố R = 0,082 atm.l.K -1. mol1 - Nu P (Pa=N/m2), V(m3) ố R = 8, 314 J.K -1. mol -1 1atm = 1, 013 10 5 Pa= 1, 013 10 5N/m2= 760 mmHg - Nu bỡnh cú mt hn hp khớ thỡ mi khớ ... hai ng: D" n1A + n2B n3C + n4D T2 D"9 D"# D "1 n1A + n2B n3C + n4D T1 Theo nh lut Hess ta cú D" = D "1 + D" # + D" !2 !1 ố D" # = ( ,1' 5 + ,2 '5 ) 4! = ( ,1' 5 + ,2 ' )4! ; : ; : !1 !2 !2 D"9 = ... ú theo nh lut Hess: -393. 513 ,57 = x - 282.989,02 x= -11 0507,81J.mol -1 Vớ d 2: Xỏc nh nng lng mng lui tinh th ca NaCl(r) bit + Nhit nguyờn t húa Na(r) D "1 = +10 8.724 % 01 Na(r) Na(h) + Nhit phõn...