Question

4) For each of the following questions circle the correct answer. There is one and only one correct answer per problem (5 points cach) a) A colligative property whose value depends directly on the mole fraction of solute particles boiling point freezing point vapor pressure osmetic pressure clevation depression lowering b) An example of a strong soluble base Pb(OH). Ba(OH)2 Cu(OH)2 леон c) A cation that is expected to act as a wcak acid in water Mg(4) d) A rate law that is second order heterogeneous ratek [AT ratek [A] [B] rate - [A] 5) The molecular complex PbCl" dissociates in water by the process PC(q) = Pb(aq) + 40 Ke-41 x 10 The initial concentration of PbClin an aqueous solution is 0.0220 M. No Portions are mally present. What is the concentration of Pb2ion present when equilibrium is achieved? [12 points)

Answer 1

of mon-volatile 4) a) vapor pressure lowering The the liquid is vapor pressure of pressure of the vapoul which is in equilibrium with that liquid. The vapour pressure solvent is lowered when solute is dissolved in it which is proportional to the mole feaction of solute. 6) Ba COH)₂ soluble base is called alkali if it contains and releases OH- ions А an e) Pb2+ (aq) 2. 2 22 It is slightly acidic in nature d) rate =K CA] CB] second ordee heterogeneous rate = k CA]² homogenous date = k CA first ordee rate =k zelo ordee 52 Pb 2 - Caq) = Caq) = Pb 2+ Pb 2+ Cag) + 40 I 0.022 M С tu tun 4 N 0.022-n n E at egom, Kc = 4.18 10-16 (n) (unde (P12+] (ce.)" (pb Cl, 2- 0.022-1 9x10184.1x10 me 256 x N o 00013