Diluting Solutions

Equation M 1 V 1 = M 2 V 2 M = Molarity V = Volume

Example 1 What volume in milliliters of a 2.00M CaCl 2 stock solution would you use to make 0.50L of 0.300M calcium chloride solution? V 1 = ? mL M 1 =2.00M V 2 =0.50L=500m L M 2 =0.300M M 1 V 1 = M 2 V (V 1 ) = 0.300(500) V 1 =75mL **Variables must have the same units!! Look to the word problem for correct number of sig. figs.

Example 2 What volume in milliliters of a 12.0M HCl solution would you use to make 2.50L of a 2.00M HCl solution? V 1 = ? mL M 1 =12.0M V 2 =2.50L=2500mL M 2 =2.00M M 1 V 1 = M 2 V (V 1 ) = 2.00(2500) V 1 =417mL

Colligative Properties  The physical properties of solutions that are different than the physical properties of a pure solvent  These depend only upon the number of particles in a solution  Vapor pressure lowering  Boiling point increasing  Freezing point lowering