Question

выпарили 200 г раствора соли 5% концентрации. Какая масса вещества осталась на стенках чаши.

Answer 1

Ответ:

Масса соли в растворе: 200×0,2=40 г. Данная масса при упаривании раствора остается неизменной.

По условию, масса раствора уменьшилась на 50 граммов и составила: 200-50=150 г.

Находим концентрацию соли в данном растворе: (40/150)×100%=26,7%

Answer 2

Calculating the Remaining Substance in the Solution

To calculate the mass of the substance remaining on the walls of the vessel after evaporating 200g of a 5% salt solution, we can use the concept of mass percentage.

Step 1: Calculate the Mass of Salt in the Solution The mass of salt in the solution can be calculated using the mass percentage formula: \[ \text{Mass of salt} = \text{Total mass of solution} \times \left( \frac{\text{Percentage of salt}}{100} \right) \]

Substituting the given values: \[ \text{Mass of salt} = 200g \times \left( \frac{5}{100} \right) = 10g \]

Step 2: Calculate the Remaining Mass of Salt When the solution evaporates, the salt remains. Therefore, the mass of the substance remaining on the walls of the vessel is the same as the mass of the salt in the solution, which is 10g.

So, the mass of the substance remaining on the walls of the vessel is 10g.