Question

к 250г. 10% раствора сульфита натрия добавили 25г. той же соли. рассчитайте массовую долю полученного раствора

Answer 1

Ответ:250 х 0.1% = 25 г рр

25 г соли + 25 г рр = 50 г

250 г + 25 г соли = 275 г общ рр

50:275=18%

Объяснение:

Answer 2

Calculation of the Mass Fraction of the Solution

To calculate the mass fraction of the solution, we need to determine the total mass of the resulting solution and the mass of the solute (sodium sulfite) in the solution.

Given: - Initial solution: 250 g of a 10% solution of sodium sulfite - Additional sodium sulfite added: 25 g

To find the total mass of the resulting solution, we add the initial mass of the solution to the mass of the additional sodium sulfite: Total mass of the resulting solution = 250 g + 25 g = 275 g

Next, we need to calculate the mass of the solute (sodium sulfite) in the resulting solution. Since the initial solution is a 10% solution, it means that 10% of the initial mass is sodium sulfite.

Mass of sodium sulfite in the initial solution = 10% of 250 g = 0.1 * 250 g = 25 g

The additional 25 g of sodium sulfite added also contributes to the mass of the solute.

Therefore, the total mass of the solute (sodium sulfite) in the resulting solution is: Total mass of sodium sulfite = 25 g (initial) + 25 g (additional) = 50 g

Finally, we can calculate the mass fraction of the resulting solution by dividing the mass of the solute by the total mass of the solution and multiplying by 100:

Mass fraction of the resulting solution = (mass of sodium sulfite / total mass of the solution) * 100 Mass fraction of the resulting solution = (50 g / 275 g) * 100 ≈ 18.18%

Therefore, the mass fraction of the resulting solution is approximately 18.18%.

Please note that the calculation assumes that the addition of the 25 g of sodium sulfite does not cause any significant change in the volume of the solution.