Question

QUESTION 10 Calculate the enthalpy, entropy and free energy of mixing one mole of toluene and two moles of benzene at 25C and latm. Assume an ideal solution

Answer 1

a. 1 mole toluene tog mole benzene at 25c and a afm *A = xp = Pressure Free everay of mixing , AG mix = MRT (XA Duna t* luxe) Total mo. of moles XA, RB mole fraction of the constituents AG mix = 3 R+ ( 4 / Putz + 21n %) = 3X8.314 x 298 (-0.766 + (-0.270)) = - 4.729 KJ Enfreoby-of mixing Asmix -- ( AG mix ) --MR (valuen txoks = 15.87 Joule kt We know that AG =AH - TAS 4H mix - 4G + TAS = (since solution behave ideally) It indicates the whole driving force of or mixing comes from the increase in entropy of the system. 15 AT1 - kg x cm 4T depressim of fx. forint is point constant 250g water contains 4g solute Cm → molal conc. (morsag) sooog 16g solute Conc = 16 , u molecular weight ATF = 0.087 Kf = 1.86 K.kg/mol Н.

- 3 0.087 1.86 X - 16X1O I mass of solate H ( = 169 = 16 x 10°Kg H = 1.86 x 16 x 103 0.087 =0.342K = 3429 . Moleculor Deight = 342 g/mole ③ Henry's law PB = botko PB bo KB vapour pressure cone. in molality Henry constant PB=2 kB =1.00 x 104 1 atm = W x 1.01 x 104 afin molecular weight of catta = 24+4= 28 g/mole - W = 2x 28 = - 5.6 x 10 3 1.01x09 5.6 X 109