Calculate the mass of sodium hydroxide contained in 500 g of 12% NaOH solution

In order to untie the task, you need to use the formula:
w = (mw / mr-ra.) * 100%, the mass of sodium hydroxide is the mass of the soluble substance (mw), the mass of the solution is 500 g, the mass fraction of the soluble substance (w).
from here mr.v. = (w * mr-ra.) / 100%;
mr.v. = (12 * 500) / 100% = 60 (g).
Answer: To prepare 500 g of a 12% sodium hydroxide solution, 60 grams will be required.