Question

Какой объем хлороводорода нужно растворить в воде для приготовления 200 смз соляной кислоты с массовой долей НС1 21,0 % и плотностью 1,10 г/смз ?

Answer 1

Решение:
m(р-раHCl)=V*P=200*1.10=220г
m(HCl)=m(р-раHCl)*w=220*0.21=46.2г
M(HCl)=36.5г/моль
n(HCl)=m/M=46.2/36.5=1.27моль
V(HCl)=n*Vm=1.27*22.4=28.45л
Ответ:28.45л

Answer 2

Calculating the Volume of Hydrochloric Acid Needed

To calculate the volume of hydrochloric acid needed to prepare 200 cm³ of hydrochloric acid solution with a mass fraction of HCl of 21.0% and a density of 1.10 g/cm³, we can use the following steps:

1. Calculate the mass of the hydrochloric acid solution: - Mass = Volume × Density - Mass = 200 cm³ × 1.10 g/cm³ - Mass = 220 g

2. Calculate the mass of HCl in the solution: - Mass of HCl = Mass of solution × Mass fraction of HCl - Mass of HCl = 220 g × 21.0% - Mass of HCl = 46.2 g

3. Calculate the volume of pure HCl needed: - Volume = Mass of HCl / Density of pure HCl - Volume = 46.2 g / (1.19 g/cm³) (density of pure HCl at 20°C) - Volume ≈ 38.82 cm³

Therefore, approximately 38.82 cm³ of pure hydrochloric acid needs to be dissolved in water to prepare 200 cm³ of hydrochloric acid solution with a mass fraction of HCl of 21.0% and a density of 1.10 g/cm³.