[FeRocks]

There is a 250 ppm solution of K+ as KCl.  You want to prepare from this a 0.00100 M solution of Cl-.  How many mL's must be diluted to 1 L? The parts per million is confusing. please help. thanks.

[Alpha-Omega]

Use the formulas I sent you


you have 250 ppm KCl solution and you want a 0.00100M solution and since K:Cl are 1:1....Oh this is cake....

so find the molarity of the 250 ppm KCl soultion....1 ppm - 1 mg/Kg or 1 mg/L so what is 250 ppm 250 mg/L  so convert that to molarity 1 g = 10^3 mg..or 10-3 g /1 mg...so .250 g/lL  you need to find the Molarity

0.250 g/L KCL x 1 mole KCl/75 g KCl= Your Molarity mol/L KClthat is the molarity of your concentrated solution

Now use M1V1 = M2V2 to get your other