Question

1. What is the conversion factor with regard to the concentrations below. For example 0.1 % by mass NaCl would be 0.1 g NaCl/100 g of solution A. 7.00 M CaCl2 B. 1.45 m KI C. 2.33% by volume chloroform in hexane D. χNaCl in water = 0.667

Answer 1

A) 7.00 M CaCl2

Molarity M = moles of solute / volume of solution in Litres

Hence,

conversion factor = 7 moles of CaCl2 / 1 L of CaCl2 solution

B) 1.45 m KI

molality m = moles of solute / mass of solvent in Kg

Hence,

conversion factor = 1.45 moles of KI / 1 Kg of solvent i.e. KI

C) 2.33 % by volume chloroform in hexane

    conversion factor = 2.33 g Chloroform /100 ml of hexane

D)   χNaCl in water = 0.667

X denotes mole fraction

mole fraction = moles of the species / total moles

      conversion factor = moles of NaCl/ ( moles of NaCl + moles of water)