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A solution of glucose in water is labelled as 10% w/w, what would be the molality and molefraction of each component in the solution ? If the density of the solution is 1.2 g mL^(-1) , thenwhat shall be the molarity of the solution ? |
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Answer» Solution :10% w/w means 10 g glucose is PRESENT in 100 g solution, Mass of water = 100 – 10 = 90 g = 0.09 kg 10 10 g glucose = 10/180 mol = 0.0555 mol Number of moles in 90 g`H_2O = 90/18 = 5` moles Molality of solution =0.0555 mol / 0.090 kg= 0.617 m Mole fraction of glucose `= (0.0555)/(5 + 0.0555) = 0.01` mole of fraction of `H_2O = 1 - 0.01 = 0.99` Volume of 100 g solution = 100/1.2 mL = 83.33 mL = 0.08333 L ` THEREFORE ` molarity `= (0.0555)/(0.08333L) = 0.67 M` |
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