Question

Choose the solvent below that would show the smallest amount of freezing point depression when used to make a 0.20 m nonelectrolyte solution carbon tetrachloride, K = 29.9°C/m chloroform, k, = 4.70"C/m ethanol, K = 1.99"Cim diethyl other, K=1.79"C/m benzene, K = 5.12 Cm

Answer 1

Using collegative property of depression in freezing point; off = 1km where, DTf = depression in freezing point i= Vont's Hoff valtor (i=1, for non electrolyte) i is basically the no. of ions a solute gives or dissociates. K = molal depression in freezing point constant for a solvent me molality of solr. (0.20m for our solar given). A). for Cely, IT = 29.9°C x 0.2008 - 5.98°C B). For CHCl3 T = 4.70°C x 0.204 = 0.94°c C). For ethanol. DTL = 1.99°C x 0.2048 = 0.39800 n D). For diethyl ether, DT = 1.7980.20 = 0.358°C E). For benzene, Str = 5.12 x 0.20 = 1.024°C Hence max. oTf is for carbon tetrachloride (cely) and He minimum DTf is for cliethyl ether (0.358°c) Thus option (e) diethyl ether, Kf = 1.79°c/un will have smallest amount of freezing point depression. Please rate the answer.