Question

The U.S. Food and Drug Administration (FDA) recommends that adults ingest less than 2.4 g of sodium per day. How many liters of softened water, containing a sodium concentration of 6.0×10−2 percent sodium by mass, have to be consumed to exceed the FDA recommendation? (Assume a water density of 1.0 g/ml).

Answer 1

0.06% Na = 0.0006 g Na/mL (since the density is 1.0 g/mL).
So 0.0006 g Na/mL x ?? mL = 2.4 g Na.
Solve for mL and convert to L.
Check my thinking.

Answer 2

An isotonic solution contains 0.88% NaCl by mass per volume. Calculate the percent mass per volume for isotonic solutions containing each of the following solutes at 15 degrees C. Assume a van't Hoff factor of 1.9 for all ionic solutes.

KCL
NaBr
Glucose