Question

14. What volume (mL) of water do I need to add to 425
mL of a 1.8 M KCl solution to make a 1.2 M solution?
How many moles of KCl are in the original solution
and how many moles of KCl are in the diluted solution?

Answer 1

Answer:

212.5 mL

both the original and the diluted solution have 0.765 moles of KCl

Explanation:

c1V1 = c2V2

V2 = c1V1/c2 = (1.8 M×425 mL)/1.2 M = 637.5 mL

(637.5 - 425) mL = 212.5 mL

n = (1.8 mol/L)(0.425 L) = 0.765 moles of KCl

since it's a dilution, the diluted solution has the same number of moles as the original solution, 0.765 moles of KCl