Question

К 360 г раствора сульфата аммония добавили избыток щелочи, полученный раствор нагрели до прекращения выделения газа. Общий объем газа составил 13,44 л (н. у. ) определите массовую долю сульфата аммония в растворе.

Answer 1

Дано:
m(р-ра NH4)2SO4) = 360 г
+NaOH
V(NH3) = 13,44 л
Найти:
ω((NH4)2SO4)=?

Vm = 22,4 л/моль
n(NH3) = 13,44 л/22,4 л/моль = 0,6 моль
M((NH4)2SO4) = 132 г/моль
(NH4)2SO4 + 2NaOH = Na2SO4 + 2NH3↑ + 2H2O
Из УХР следует, что n((NH4)2SO4) = 0,5n(NH3)
n((NH4)2SO4) = 0,5*0,6 моль = 0,3 моль
m((NH4)2SO4) = 0.3 моль*132 г/моль = 39,6 г
ω((NH4)2SO4) = 39.6 г/360 г =  0,11 или 11%
Ответ: 11%

Answer 2

Calculation of the Mass Fraction of Ammonium Sulfate in the Solution

To determine the mass fraction of ammonium sulfate in the solution, we need to use the given information. Let's break down the steps:

1. A 360 g solution of ammonium sulfate was prepared. 2. An excess of alkali was added to the solution. 3. The resulting solution was heated until the gas evolution ceased. 4. The total volume of gas produced was 13.44 L at standard temperature and pressure (STP).

To calculate the mass fraction of ammonium sulfate, we need to know the molar mass of ammonium sulfate (NH4)2SO4. The molar mass of ammonium sulfate is the sum of the atomic masses of its constituent elements:

- Nitrogen (N): 14.01 g/mol - Hydrogen (H): 1.01 g/mol - Sulfur (S): 32.07 g/mol - Oxygen (O): 16.00 g/mol

The molar mass of ammonium sulfate is calculated as follows:

(2 * 14.01 g/mol) + (8 * 1.01 g/mol) + 32.07 g/mol + (4 * 16.00 g/mol) = 132.14 g/mol

Now, let's calculate the mass of ammonium sulfate in the solution:

Mass of ammonium sulfate = (Volume of gas at STP * Molar mass of ammonium sulfate) / 22.4 L/mol Mass of ammonium sulfate = (13.44 L * 132.14 g/mol) / 22.4 L/mol

Mass of ammonium sulfate = 79.68 g

Finally, let's calculate the mass fraction of ammonium sulfate in the solution:

Mass fraction of ammonium sulfate = (Mass of ammonium sulfate / Mass of solution) * 100

Mass fraction of ammonium sulfate = (79.68 g / 360 g) * 100

Mass fraction of ammonium sulfate ≈ 22.13%

Therefore, the mass fraction of ammonium sulfate in the solution is approximately 22.13%.

Please note that the calculations provided above are based on the given information and assumptions.