Percent by mass solution

Question

Percent by mass solution

Imagine you need to prepare 48.1 grams of a NaCl solution that is 0.72% by mass. 

Question: Calculate the mass (in grams) of NaCl that is needed to make this solution.

Answer 1

0.72% by mass NaCl:

48.1 g x 0.0072 = 0.346 g NaCl = mass of NaCl needed

Now, if you actually meant 72% by mass, then it would be...

48.1 g x 0.72 = 34.6 g NaCl needed