Question

Определите массу карбоната кальция, содержащегося в 10 г мела, имеющего 15% примесей.К 60 г 10 % раствора соли добавили ещё 10 г соли. Определите массовую долю соли в полученном при этом растворе

Answer 1

1) примесей - 15%
    ч. CaCO₃ - 85%
10г - 100% 
 хг  -  85%
х = (85г * 10%) / 100% = 8,5 г

2) m₁(соли) = 60г * 0,1 = 6г
m(соли) = 6г +10г = 16г
m₂(р-ра) = 60г + 10г = 70г
W₂(соли) = 16г / 70г = 0,229 ; 22,9%

Answer 2

Calculation of Calcium Carbonate Mass in Chalk

To determine the mass of calcium carbonate in 10 g of chalk with 15% impurities, we need to calculate the mass of pure calcium carbonate.

Let's assume that the mass of pure calcium carbonate in 10 g of chalk is x grams.

According to the given information, the chalk contains 15% impurities. This means that the remaining 85% is pure calcium carbonate.

We can set up the following equation to find the mass of pure calcium carbonate:

x = 0.85 * 10 g

Simplifying the equation, we find:

x = 8.5 g

Therefore, the mass of pure calcium carbonate in 10 g of chalk is 8.5 grams.

Calculation of Salt Mass in the Solution

Next, let's calculate the mass of salt in the solution.

Initially, we have a 60 g solution with a concentration of 10%.

This means that the solution contains 10% salt and 90% solvent.

We can calculate the mass of salt in the initial solution as follows:

Mass of salt in the initial solution = 10% * 60 g = 6 g After adding an additional 10 g of salt to the solution, the total mass of salt becomes:

Total mass of salt = 6 g + 10 g = 16 g

Calculation of Salt Mass Fraction in the Resulting Solution

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

The resulting solution is the sum of the initial solution (60 g) and the additional 10 g of salt:

Total mass of resulting solution = 60 g + 10 g = 70 g

The mass fraction of salt in the resulting solution can be calculated as follows:

Mass fraction of salt = (mass of salt in the resulting solution / total mass of resulting solution) * 100%

Substituting the values, we find:

Mass fraction of salt = (16 g / 70 g) * 100% ≈ 22.86%

Therefore, the mass fraction of salt in the resulting solution is approximately 22.86%.