Question

После пропускания через раствор гидроксида натрия 2,24 л сернистого газа (н.у.) получили 252 г раствора сульфита натрия. Вычислите массовую долю соли в полученном растворе.

Answer 1

2NaOH+SO2=Na2SO3+H2O
n(SO3)=2.24/22.4=0.1 моль
по уравнению реакции на 1 моль приходится  1 моль сульфита натрия
значит n(Na2SO3)=n(SO2)=0.1 моль
Mr(Na2SO3)=46+32+48=126
m(Na2SO3)=126*0.1=12.6 г
w=12.6/252*100%=5%

Answer 2

Calculation of the Mass Fraction of Sodium Sulfite in the Solution

To calculate the mass fraction of sodium sulfite in the solution, we need to determine the mass of sodium sulfite and the total mass of the solution.

Given: - Volume of sulfur dioxide gas (at standard conditions): 2.24 L - Mass of the resulting sodium sulfite solution: 252 g

To calculate the mass fraction, we can use the formula:

Mass Fraction = (Mass of Sodium Sulfite) / (Total Mass of Solution)

Let's calculate the mass of sodium sulfite first.

From the given information, we know that the volume of sulfur dioxide gas (at standard conditions) is 2.24 L. However, we need to convert this volume to the number of moles of sulfur dioxide gas using the ideal gas law.

Using the molar volume of an ideal gas at standard conditions (22.4 L/mol), we can calculate the number of moles of sulfur dioxide gas:

Number of Moles of Sulfur Dioxide = (Volume of Sulfur Dioxide Gas) / (Molar Volume of Ideal Gas at Standard Conditions)

Number of Moles of Sulfur Dioxide = 2.24 L / 22.4 L/mol

Now, we need to determine the molar ratio between sulfur dioxide and sodium sulfite. From the balanced chemical equation for the reaction between sulfur dioxide and sodium hydroxide, we know that the molar ratio is 1:1.

Therefore, the number of moles of sodium sulfite is equal to the number of moles of sulfur dioxide.

Now, we can calculate the mass of sodium sulfite using its molar mass.

Mass of Sodium Sulfite = (Number of Moles of Sodium Sulfite) * (Molar Mass of Sodium Sulfite)

To calculate the total mass of the solution, we use the given mass of the resulting sodium sulfite solution, which is 252 g.

Now, we can calculate the mass fraction of sodium sulfite in the solution using the formula mentioned earlier.

Mass Fraction = (Mass of Sodium Sulfite) / (Total Mass of Solution)

Let's perform the calculations:

1. Calculate the number of moles of sulfur dioxide: - Number of Moles of Sulfur Dioxide = 2.24 L / 22.4 L/mol = 0.1 mol 2. Calculate the mass of sodium sulfite: - Mass of Sodium Sulfite = 0.1 mol * Molar Mass of Sodium Sulfite

3. Calculate the mass fraction of sodium sulfite: - Mass Fraction = (Mass of Sodium Sulfite) / (Total Mass of Solution) = (Mass of Sodium Sulfite) / 252 g

Please provide the molar mass of sodium sulfite so that we can proceed with the calculations.