Question

Рассчитайте массовую долю( в процентах) хлороводорода в 400 г соляной кислоты, если в ней максимально растворяется 5,4 г металлического алюминия.

Answer 1

2Al + 6HCl= 2AlCl + 3H2 n(Al) = m/M = 5.4 г. / 27 г/моль = 0,2 моль  n(HCl) = 0.6 моль m(HCl) = M * n = 36.5 * 0.6 моль = 21,9 г. w = m/V * 100% = 21.9 / 400 * 100% = 5.475 % Ответ : 5,475%

Answer 2

Calculating the Mass Fraction of Hydrochloric Acid in 400g of Hydrochloric Acid Solution

To calculate the mass fraction of hydrochloric acid in the solution, we can use the following formula:

Mass Fraction = (Mass of HCl / Total Mass of Solution) * 100%

Given: - Mass of aluminum that can be dissolved in the solution = 5.4g - Total mass of the solution = 400g

Using the given information, we can calculate the mass fraction of hydrochloric acid in the solution.

Calculations: - Mass of HCl = Mass of aluminum that can be dissolved = 5.4g - Total mass of the solution = 400g

Mass Fraction of HCl = (5.4g / 400g) * 100%

Mass Fraction of HCl = (5.4 / 400) * 100%

Mass Fraction of HCl ≈ 1.35%

Therefore, the mass fraction of hydrochloric acid in the 400g solution is approximately 1.35%.