Question

Вычислить объем раствора хлорида натрия с массовой долей 14,6% и плотностью 1,12 г/мл,при полном электролизе которого можно получить 125 г гидроксида натрия (ответ: 1,12 л)

Answer 1

2NaCl+2H2O = Cl2 +H2 + 2NaOH
n(NaOH) = 125г/40г/моль=3,125 моль; n(NaCl) = n(NaOH) = 3,125 моль.
m(NaCl) = 3,125 моль*58,5 г/моль =182,8 г;
m(р-ра) = 182,8 г*100%/14,6% =1252,05 г;
V(р-ра NaCl) = 1252,05 г/1,12 г/мл =1118 мл = 1,118л

Answer 2

Calculation of Sodium Chloride Solution Volume

To calculate the volume of a sodium chloride solution with a mass fraction of 14.6% and a density of 1.12 g/mL, we need to use the given information about the electrolysis of the solution to determine the amount of sodium hydroxide produced.

According to the information provided, when the sodium chloride solution is fully electrolyzed, it produces 125 g of sodium hydroxide.

To find the volume of the sodium chloride solution, we can use the following steps:

1. Calculate the mass of the sodium chloride in the solution: - The mass fraction of sodium chloride is given as 14.6%, which means that 100 g of the solution contains 14.6 g of sodium chloride. - Let's assume the mass of the sodium chloride solution is M g. - Therefore, the mass of sodium chloride in the solution can be calculated as (14.6/100) * M g.

2. Calculate the volume of the sodium chloride solution: - The density of the solution is given as 1.12 g/mL. - Let's assume the volume of the sodium chloride solution is V mL. - Therefore, the mass of the sodium chloride solution can be calculated as V mL * 1.12 g/mL.

3. Set up an equation using the mass of sodium chloride and the mass of the sodium chloride solution: - The mass of sodium chloride in the solution should be equal to the mass of the sodium chloride solution. - (14.6/100) * M g = V mL * 1.12 g/mL.

4. Solve the equation for V to find the volume of the sodium chloride solution.

Let's calculate the volume of the sodium chloride solution using the given information.

Step 1: Calculate the mass of sodium chloride in the solution: - The mass fraction of sodium chloride is 14.6%. - Let's assume the mass of the sodium chloride solution is M g. - Therefore, the mass of sodium chloride in the solution is (14.6/100) * M g.

Step 2: Calculate the volume of the sodium chloride solution: - The density of the solution is 1.12 g/mL. - Let's assume the volume of the sodium chloride solution is V mL. - Therefore, the mass of the sodium chloride solution is V mL * 1.12 g/mL.

Step 3: Set up the equation: - The mass of sodium chloride in the solution should be equal to the mass of the sodium chloride solution. - (14.6/100) * M g = V mL * 1.12 g/mL.

Step 4: Solve for V: - Rearranging the equation, we have V = ((14.6/100) * M g) / (1.12 g/mL).

Now, we can substitute the given value of 125 g for the mass of sodium hydroxide and solve for V.

V = ((14.6/100) * M g) / (1.12 g/mL) 125 g = ((14.6/100) * M g) / (1.12 g/mL)

Simplifying the equation, we find: M g = (125 g * 1.12 g/mL) / (14.6/100)

Calculating the value of M, we get: M ≈ 963.01 g

Therefore, the volume of the sodium chloride solution is approximately 963.01 mL, which is equivalent to 0.96301 liters.