Using calculations, determine how you would make a 525 ml pg a 0.50 M solution of Cl- ions using CaCl2.

Question

I am unsure how to do this question, I was going to use C1V1=C2V2 but with this I would be missing the first part of the equation. If that is the case, would I assume the solution was originally 1 M CaCl2 and find the volume necessary to make 525 ml of a 0.50 M solution?

C1V1=C2V2
(1 M)(V1)=(0.50 M)(525 ml)
V1 = (0.50 M)(525 ml)/(1 M)
V1 = 262.5 ml of 1 M CaCl2.

Answer 1

525 mL of .5 M solution contains
(.525 * .5) moles of solute

since you get 2 Cl-ions from each CaCl₂
you will need...(.525 * .5 * .5) moles of CaCl₂, dissolved in 525 mL of solution
molar mass of CaCl₂ is 111 g

(.5 * .5 * .525 * 111) g of CaCl₂