Question

How much distilled water must be added to .85% solution Of NaCL to make a 70% solution of NaCl

Answer 1

You may have meant 85% but you typed .85%. You can't make 70% NaCl from 0.85% by adding water to it.

Answer 2

I meant 0.85% and 0.70% ...sorry

Answer 3

c1v1 = c2v2