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The work of an experiment with a certain concentration of a certain salt:

When it is mentioned, for example, that what is required is to make a solution of 100 cm of a certain salt, so that the degree of concentration of the solution is 10, for example, this means that the volume of the solution should be “. 100 3) Considering that these ten grams of salt do not occupy a volume of 10 cm, so the 90 cm must be completed. The final solution is 100 cm.

If it is required to make a solution (volume of 100 cm, for example) of a specific acid (such as concentrated hydrochloric, acetic, or sulfuric acid, for example), and the degree of concentration is 10%, then this is done by adding 10% of the acid to 90 cm of water directly. The following table shows the weight of the salts needed to make solutions of a certain concentration.

Making a solution of a certain concentration from two other solutions that differ in their concentration:

Assuming that we have two solutions that differ in their degree of concentration, as if the degree of concentration of the first is 30% and the degree of concentration of the second is 8%, and it is required to prepare a third solution of which the degree of concentration is only 10%.

(a) The degree of concentration of the first solution is written on the upper left side, the degree of concentration of the second solution is written on the upper right side, and the degree of concentration of the required solution is written at the bottom - in a middle place.

(b) The number denoting the degree of concentration of the new test required is subtracted from the number denoting the degree of concentration of the first solution that is already present. So, according to what is shown in the figure, subtract the number 10 from 20, i.e. 20 - 10 = 10 parts of the first solution.

(H) Then the number indicating the degree of concentration of the second solution is subtracted from the number indicating the degree of concentration of the required new solution. According to what is shown in the figure, the number 8 is subtracted from the number 10, i.e. 10 - 8 = 2 part of the second solution.

In order for the degree of concentration of the new solution = 10%, only 10 parts of the first solution must be mixed with two parts of the second solution.

Diluting a solution of a certain concentration to a lower concentration:

In the same way as previously shown in Figure 31, any solution of a certain concentration (such as (15) can also be diluted to another concentration lower than the above (such as 5%), then the following steps are followed, which we explain in Figure 32.

(1) Write in the left corner the degree of concentration of the solution that actually exists.
(b) It is written in the right corner. It denotes the degree of concentration of water.
(H) Write in the middle the degree of concentration of the required new solution.
(D) The number indicating the degree of concentration of the required solution shall be subtracted from the number indicating the concentration of the actual solution.

That is, 15 - 5 = 10 parts of the original solution. (e) The number indicating the degree of water concentration (which is .) is subtracted from the number indicating the degree of concentration of the required solution (which is 5%)
That is, 5% - 0% = e parts of water.
To dilute a solution from 15 to 0% only, ten parts of a concentrated solution (15%) must be added to five parts of water.