50 ~g of a substance is dissolved in 1 ~kg of water at +90^ C . The temperature is reduced to +10^ C . The density is increased from 1.1 to 1.15 ~g cc ⁻¹ . What is the % change of molarity of the solution?

Step-by-step solution

Molarity = Weight dissolved Molar mass 1000 V( ~mL ) and V= Mass of solution Density Molarity (1) at 90^ C = 50 x 1000 1.1 1050 = 52.38 x Molarity (2) at 10^ C = 50 x 1000 1.15 1050 = 54.76 x Change in molarity = Molarity (2) - Molarity (1) % change in molarity will be = Molarity (2)- Molarity (1) Molarity (1) 100= 54.76 x - 52.38 x 52.38 x 100= 2.38 x x 52.38 100=4.5