A big irregular shaped vessel contained water, conductivity of which was 2.56 × 10^–3 S m^–1. 585 g — Electrochemistry Chemistry Question
Question
A big irregular shaped vessel contained water, conductivity of which was 2.56 × 10^–3 S m^–1. 585 g of NaCl was then added to the water and conductivity after the addition of NaCl, was found to be 3.06 × 10^–3 S m^–1. The molar conductivity of NaCl at this concentration is 1.5 × 10^–2 S m^2 mol^–1. The capacity of vessel if it is fulfilled with water, is
💡 Solution & Explanation
Specific conductance contributed by NaCl (κ) = κ_final - κ_water = (3.06 - 2.56) × 10^–3 = 0.50 × 10^–3 S m^–1. Since Λ_m = κ / C, concentration C = κ / Λ_m = (0.50 × 10^–3) / (1.5 × 10^–2) = 1/30 mol/m^3. Mass of NaCl = 585 g, which is 585 / 58.5 = 10 moles. Volume of the vessel V = moles / C = 10 / (1/30) = 300 m^3. Since 1 m^3 = 1000 L, V = 300 × 1000 = 300,000 L = 3 × 10^5 L. Therefore, correct answer is D.