Question #1b7e2

1 Answer
Feb 2, 2018

This solution is supersaturated. Explanation below...

Explanation:

The graph you have reads "g of solute per 100 g H2O. Therefore, the information we are given (42 g in 50 mL) needs to be altered.

The same rate of dissolving would result in 84 g in 100 g H2O

Now, find 84 g on the vertical scale, and draw a horizontal line from that point across the graph. Then draw a vertical line up from 30 °C, and you will see that the intersection of these lines is at a point above and to the left of the green curve for KNO3.

Being in this region means that the amount of solute is greater than the saturation point (which would fall on the curve - at about 44 g at 30°C) for KNO3.

Therefore, the solution is supersaturated - an unstable situation in which you manage to dissolve more solute than saturation would seem to allow!