Question

К 140 г раствора с массовой долей хлорида натрия 12 % добавили 20 мл воды и 14 г этой же соли. Определите массовую долю соли в полученном растворе

Answer 1

Лучше поэтапно написать, так как масса раствора и соли изменяется.

Answer 2

Calculation of Mass Fraction of Salt in the Solution

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

Given information: - Initial solution mass: 140 g - Mass fraction of sodium chloride in the initial solution: 12% - Volume of water added: 20 mL - Mass of sodium chloride added: 14 g

To calculate the mass fraction of salt in the resulting solution, we can follow these steps:

1. Calculate the mass of the initial solution: - Mass of the initial solution = Initial solution mass - Mass of sodium chloride added - Mass of the initial solution = 140 g - 14 g = 126 g

2. Calculate the mass of the resulting solution: - Mass of the resulting solution = Mass of the initial solution + Mass of water added - Mass of the resulting solution = 126 g + 20 g = 146 g

3. Calculate the mass of the salt in the resulting solution: - Mass of the salt in the resulting solution = Mass of sodium chloride added - Mass of the salt in the resulting solution = 14 g

4. Calculate the mass fraction of salt in the resulting solution: - Mass fraction of salt = (Mass of the salt in the resulting solution / Mass of the resulting solution) * 100% - Mass fraction of salt = (14 g / 146 g) * 100% ≈ 9.59%

Therefore, the mass fraction of salt in the resulting solution is approximately 9.59%.

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