Question

В 120 г воды растворили 80 г щелочи найти массовую долю?

Answer 1

Масса раствора = масса воды+масса щелочи = 120+80=200г
массовая доля = массу щелочи / массу раствора *100%=80/200*100%=40%
ответ 40%

Answer 2

Calculation of Mass Fraction

To find the mass fraction of a solution, we need to divide the mass of the solute (in this case, the alkaline substance) by the total mass of the solution (which includes both the solute and the solvent, in this case, water).

Given that 120 grams of water were dissolved with 80 grams of alkaline substance, we can calculate the mass fraction as follows:

Mass of Solute: 80 grams Mass of Solution: 120 grams + 80 grams = 200 grams

Mass Fraction = (Mass of Solute / Mass of Solution) * 100

Mass Fraction = (80 grams / 200 grams) * 100 = 40%

Therefore, the mass fraction of the alkaline substance in the solution is 40%.

Please note that the calculation assumes that the alkaline substance is completely dissolved in water and that there are no other components present in the solution.