5l of a 10 m concentrated stock solution is diluted to 3 m. what is the final volume of the solution?

THis is a C1V1 = C2V2 calculation. We are given the initial concentration (10 M), the initial volume (0.5 L) and the final concentration (3 M) From this we are told to calculate the final volume of solution, therefore:

(10 M)(0.5) = (3 M)(V2)
V2 = 1.66 L