Question

To what volume (in mL) should you dilute 48.5 mL of a 5.85 M KI solution so that 28.5 mL of the diluted solution contains 2.55 g of KI. Show all work.

Answer 1

since 28.5 mL of the diluted solution contains 2.55 g of KI, let us find the final molarity of solution

Molar mass od KI=166 gm
number of moles= mass /molar mass
     =2.55/166
     = 0.01536 mol

final concentration , M2 = number of moles/ volume in L
                           = 0.01536/0.0285
                           = 0.539 M

use:
M1*V1=M2*V2
5.85*48.5 = 0.539 * V2
V2=526.4 mL

Ans:526.4 mL