Calculate the molality of KI if the density of 20% (mass/mass) aqueous KI is 1.202 gmL -1 . Report your final answer by rounding off the molality correct upto one place of decimal and then multiplying it by 10.

Step-by-step solution

Weight of KI in 100g of water = 20 g Weight of water in the solution = 100 - 20 = 80 g= 0.08 kg Molar mass of KI = 39 + 127 = 166 g mol -1 Molality of the solution (m) = Number of moles of KI Mass of water in kg = 2 0 g / 1 6 6 g mol - 1 0 · 0 8 kg = 1.506 mol kg -1 = 1.506 m By rounding off to one place, we get the molality as 1.5 and by further multiplying it with 10, we get "15" as the final answer.