1) The conductance of a 0.0015 M aqueous solution of a weak monobasic acid was determined by using a conductivity cell consisting of platinised pt electrodes. The distance between the electrodes is 120 cm with an area of cross section of 1 cm2. The conductance of this solution was found to be 5× 10-7 S. The pH of the solution is 4. The value of limiting molar conductivity ( ∧0m) of this weak monobasic acid in aqueous solution is Z× 102 S cm-1 mol-1. The value of Z is A) 600 B) 800 C) 500 D) 400 Answer: Option AExplanation: pH = C α=10−4 ⇒ α=10−4.0015 Also, onductance (G)= K(AI) ⇒ K=G(IA)=5×10−7×1201=6×10−5 ⇒ ∧c=k×1000C = 6×10−5×1000.0015 ⇒ ∧∞=∧cα=6×10−5×1000.0015×0.001510−4 =600=6 x102 S cm-1 mol-1