If 500 mL of a 5M solution is diluted to 1500 mL, what will be the molarity of the solution obtained?
The molarity M of a solution is inversely proportional to its volume V, if the mass of the solute is kept the same. Hence, the formula is established M1V1 = M2V2.
Using this formula, where M1 is the initial molarity of the solution = 5M,
V1 is the initial volume of the solution = 0.5L,
V2 is the final volume of the solution = 1.5L
M2 is the final volume of the solution =?
Substituting these values, 5 x 0.5 = M2 x 1.5
Therefore, M2 = 1.66M.
The correct answer is (ii).