Question

A solution is saturated when 25.0 grams of the solute is dissolved in 100.0 grams of solvent. When a new solution is made that has 40.0 grams of solute dissolved in 160 grams of solvent, assuming a constant temperature, classify the new solution as:

Answer 1

The new solution with 40 grams of solute in 160 grams of solvent is saturated, as it has the same concentration of solute per 100 grams of solvent as the original saturated solution.

Step-by-step explanation:

When a solution reaches the point where no additional solute will dissolve, it is considered saturated. In the student's original solution, 25 grams of solute in 100 grams of solvent represents a saturated solution. If a new solution contains 40.0 grams of solute in 160 grams of solvent, we must compare the concentration of solute to the solvent's ability to dissolve that solute at a given temperature. Assuming temperature is constant and solubility does not change, the new solution can be compared to the original by calculating the concentration of solute per 100 grams of solvent. In the original solution, the saturated concentration is 25 grams of solute per 100 grams of solvent. In the new solution, adjusting to per 100 grams of solvent, we have 25 grams of solute per 100 grams of solvent (since (40 grams/160 grams)*100 equals 25). This means the new solution has the same concentration as the original saturated solution, and thus, it is also saturated.

Answer 2

Satured

Step-by-step explanation:

A solution can be classified as unsaturated, saturated or supersaturated. The solvent has a maximum capacity of dissolution, so when it hasn't reached this capacity, the solution is unsaturated, when it reaches it, the solution is saturated, and when it surpasses this capacity, the solution is supersaturated.

To know the classification of a solution, we must know it's solubility coefficient, which can be calculated by dividing the amount of solute by the amount of solvent. Usually it is given by the mass of solute/100 mL of solvent, but in this case, let's calculate it in the mass of solute/mass of solvent.

When 25.0 g of solute is dissolved in 100.0 g of the solvent the solution is saturated, so the solubility coefficient will be:

25/100 = 0.25 g/g

It means that, if the mass of solute/ mass of solvent is lower than 0.25, the solution is unsaturated, if it's higher, supersaturated, and if it's equal to 0.25, saturated.

So, for 40.0 g of solute and 160.0 g of solvent:

40/160 = 0.25 g/g

And the solution is saturated.