Question

На полную нейтрализацию 100г раствора соляной кислоты потребовалось 40г 10%ного раствора гидроксида натрия. Рассчитайте массовую долю кислоты в исходном растворе

Answer 1

...........................

Answer 2

Calculation of the Mass Fraction of Acid in the Initial Solution

To calculate the mass fraction of acid in the initial solution, we need to determine the amount of acid and the total mass of the solution.

Given: - Mass of the hydrochloric acid solution (HCl) = 100 g - Mass of the sodium hydroxide solution (NaOH) = 40 g - Concentration of the sodium hydroxide solution = 10%

To find the amount of acid neutralized by the sodium hydroxide solution, we can use the equation:

Amount of acid neutralized = Concentration of sodium hydroxide solution × Mass of sodium hydroxide solution

Substituting the given values:

Amount of acid neutralized = 10% × 40 g = 4 g

Since the amount of acid neutralized is equal to the amount of acid in the initial solution, the mass fraction of acid can be calculated as:

Mass fraction of acid = (Amount of acid neutralized / Mass of the initial solution) × 100%

Substituting the values:

Mass fraction of acid = (4 g / 100 g) × 100% = 4%

Therefore, the mass fraction of acid in the initial solution is 4%.