Question

Определите массу соли сульфата калия необходимую для получения раствора с массовой долей 14%, если полученную массу соли растворить в 300 мл воды. Ответ приведите с точностью до целых.

Answer 1

Ответ:

49

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Answer 2

Calculating the Mass of Potassium Sulfate Needed

To determine the mass of potassium sulfate required to obtain a solution with a mass fraction of 14% when the obtained mass of the salt is dissolved in 300 ml of water, we can use the following steps:

1. Calculate the Mass of the Solution: - The mass of the solution can be calculated using the mass fraction and the volume of the solution.

2. Calculate the Mass of Potassium Sulfate: - Once the mass of the solution is known, the mass of potassium sulfate needed can be calculated based on the mass fraction.

Calculation Steps

1. Calculate the Mass of the Solution: - Given: Mass fraction = 14%, Volume of water = 300 ml - Using the mass fraction formula: Mass of solution = Mass of salt / (Mass of salt + Mass of water) - We can rearrange the formula to find the mass of the solution: Mass of solution = (Mass fraction * Volume of solution) / (100 - Mass fraction) - Substituting the given values: Mass of solution = (14 * 300) / (100 - 14)

Calculation: - Mass of solution = (14 * 300) / (100 - 14) - Mass of solution = (4200) / (86) - Mass of solution ≈ 48.8372 g

2. Calculate the Mass of Potassium Sulfate: - Now that we know the mass of the solution, we can calculate the mass of potassium sulfate needed to achieve the desired mass fraction. - Mass of potassium sulfate = Mass of solution * (Mass fraction / 100) - Substituting the values: Mass of potassium sulfate = 48.8372 * (14 / 100)

Calculation: - Mass of potassium sulfate = 48.8372 * (14 / 100) - Mass of potassium sulfate ≈ 6.837 g

Therefore, the mass of potassium sulfate needed to obtain a solution with a mass fraction of 14%, when the obtained mass of the salt is dissolved in 300 ml of water, is approximately 6.837 grams.