Question

Given that sodium chloride is 39.0% sodium by mass, how many grams of sodium chloride are needed to have 100.mg of Na present? Given that sodium chloride is 39.0% sodium by mass, how many grams of sodium chloride are needed to have of Na present? a. 0.256 b. 256 c. 39.0 d. 0.0390 e. none of the above

Answer 1

Answer: The mass of sodium chloride solution present is 0.256 grams.

Explanation:

We are given:

39.0 % of sodium in sodium chloride solution

This means that 39.0 grams of sodium is present in 100 grams of sodium chloride solution

Mass of sodium given = 100 mg = 0.1 g     (Conversion factor:  1 g = 1000 mg)

Applying unitary method:

If 39 grams of sodium metal is present in 100 grams of sodium chloride solution

So, if 0.1 grams of sodium metal will be present in = $\frac{100}{39}\times 0.1=0.256g$ of sodium chloride solution.

Hence, the mass of sodium chloride solution present is 0.256 grams.