How many milliliters of 10.5 M HCl(aq) are needed to prepare 785.0 mL of 1.00 M HCl(aq)?

Answer 1

For many such dilution problems, you can use V1M1 = V2M2.

V1 = initial volume = ?

M1 = initial molarity = 10.5 M

V2 = final volume = 785.0 ml

M2 = final molarity = 1.00 M

(x ml)(10.5 M) = (785.0 ml)(1.00 M)

x = 74.76 mls = 74.8 mls (3 sig. figs.)