Question

Сколько граммов соляной кислоты содержится в 250 мл 15 % раствора HCL,если плотность раствора равна 1,035 г/см в кубе.Рассчитайте моляльную и моля оную концентрации.

Answer 1

Mр-ра(HCl)=V*p=250*1.035=259 г
m(HCl)=mp-pa*ω=259*0.15=39 г
V=250мл=0,25л
С=m/(V*M)=39/(0,25*36.5)=4,3 моль/л
m(растворителя) = m(p-pa) - m(раств.в-ва)
m(растворителя) =259-39=220г=0,22кг
m(моляльность)=m/M*m(растворителя)=39/(36,5*0,22)=4,86 моль/кг

Answer 2

Calculating the Amount of Hydrochloric Acid in 250 ml of 15% HCl Solution

To calculate the amount of hydrochloric acid in 250 ml of 15% HCl solution, we can use the formula:

Amount of HCl (in grams) = Volume of solution (in ml) × Concentration of HCl (in %) × Density of solution (in g/cm³) / 100

Substituting the given values: - Volume of solution (V) = 250 ml - Concentration of HCl (C) = 15% - Density of solution (D) = 1.035 g/cm³

We can calculate the amount of hydrochloric acid in grams using the above formula.

Amount of HCl (in grams) = 250 ml × 15% × 1.035 g/cm³ / 100

Amount of HCl (in grams) = 250 ml × 0.15 × 1.035 g / 100

Amount of HCl (in grams) = 3.875 grams

So, there are 3.875 grams of hydrochloric acid in 250 ml of 15% HCl solution.

Calculating Molar and Molal Concentrations

Now, let's calculate the molar and molal concentrations of the 15% HCl solution.

Molar Concentration (Molarity):

The molar concentration (M) can be calculated using the formula:

M = (moles of solute) / (volume of solution in liters)

First, we need to calculate the moles of HCl in the solution.

Moles of HCl = (mass of HCl) / (molar mass of HCl)

The molar mass of HCl is approximately 36.46 g/mol.

Moles of HCl = 3.875 g / 36.46 g/mol

Moles of HCl ≈ 0.1063 moles

Now, we can calculate the molar concentration (Molarity) using the formula:

M = 0.1063 moles / (250 ml / 1000)

M ≈ 0.4252 M

So, the molar concentration (Molarity) of the 15% HCl solution is approximately 0.4252 M.

Molal Concentration:

The molal concentration can be calculated using the formula:

Molality (m) = (moles of solute) / (mass of solvent in kg)

Since the density of the solution is 1.035 g/cm³, we can convert the volume of the solution to mass of the solution and then calculate the molality.

Mass of solution = Volume of solution × Density of solution

Mass of solution = 250 ml × 1.035 g/ml

Mass of solution = 258.75 grams

Now, we can calculate the molality:

Molality (m) = 0.1063 moles / (258.75 g / 1000)

Molality (m) ≈ 0.4104 m

So, the molal concentration of the 15% HCl solution is approximately 0.4104 m.