Question

Given that sodium chloride is 39.0% sodium by mass, how many grams of sodium chloride are needed to have 950.mg of na present?

Answer 1

39 % = 950 mg = 0.75 g 
100 % = ? 

? = 100 / 39 * 0.95 = 2.44g or 2.4358974 of NaCl

Answer 2

Answer:

2.4358 grams of sodium chloride have 950.mg of sodium.

Explanation:

Percentage of sodium in sodium chloride = 39.0 \%

Given mass of the sodium = 950 mg = 0.950 g

Let the mass of sodium chloride be M

Percentage of sodium:

$39.0\%=\frac{0.950 g}{M}\times 100$

M = 2.4358 g

2.4358 grams of sodium chloride have 950.mg of sodium.