Determine the mass fraction of salt in the solution if 80 g of water and 20 g of salt were taken for its preparation.

Let’s calculate the weight of the solution. To do this, add the masses of water and salt.

M solution = M water + M salt = 80 + 20 = 100 grams;

The mass fraction of the component of the solution will be equal to the ratio of its weight to the weight of the solution.

Let’s find the concentration of salt in the solution.

With salt = 20/100 = 0.2 = 20%;

Let’s find the concentration of water in the solution.

From water = 80/100 = 0.8 = 80%;

Let’s check:

To do this, we sum up the concentrations of the components of the solution.

20 + 80 = 100;



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