Part 1.1: Analytical Chemistry, Questions and answers on Solutions and Concentrations

Questions and answers on Solutions and Concentrations. Calculation of the Molarity, Molality and the Normality. 1. What is the molarity when 0.75 mol dissolved in 2.5L of solution? 2.Calculate the molarity of 25g KBr dissolved in 750 ml of water 3.How many gram of KCl are needed to prepare 125 ml of 0.72 M KCl solution 4.What is the volume of 4 M solution made using 100 g of lithium bromide 5.A solution is prepared by mixing 1 g of ethanol (C2H5OH) with 100 g water to give a final volume of 101 mL. Calculate the molarity, mass percent, mole fraction, and molality of ethanol in this solution. 6.The electrolyte in automobile lead storage batteries is a 3.75 M sulfuric acid solution that has a density of 1.23 g/ml. Calculate the mass percent, molality, and normality of the sulfuric acid. 7.Calculate the normality of 0.74 g of calcium hydroxide in 10 ml of solution 8.Calculate the normality of 13.4 g of sodium oxalate in a 100 mL solution. 9.The stock solution available in your reagent chemical store has the following indication: dangerous, corrosive, toxic, harmful, density: 1.84g/cm3; percentage: 98%; molecular weight: 98g/mol; H2SO4 . Calculate its molarity and normality. Explain how will you prepare 2 M sulfuric acid solution from this stock solution having in your disposition 100 ml flak. 10.175 mL of a 1.6 M aqueous solution of LiCl is diluted with water to a final volume of 1.0 L. What is the final concentration of the diluted solution? 11.In order to generate a calibration curve for iron, a student needs to prepare different solutions containing iron with known concentrations. He has a standard solution of 100 mg/l of iron in the stock. Explain how, will he prepare 0.2, 0.4, 0.8 and 1 mg/l of iron standards from 100 mg/l. The student has only 100 ml flasks in the laboratory.