Hi, my question is:

"Classify each of the following as saturated, supersaturated, or unsaturated:

KNO3 90g/100g at 82*C
NaCl 36g/100g at 23*C
KCl 35g/100g at 18*C
NaNO3 90g/100g at 28*C

How do I determine if they are saturated, supersaturated, or unsaturated?

Since the question is so specific regarding temperature, you must have some data you have collected or that is a part of your work (such as an experiment). You don't mention the solvent? Is it water? And is the solvent the grams of solvent or grams of solution? For example, should the first one read 90 g KNO3 in 100 g water or 90 g KNO3 in 100g of solution? Look in your reference for the solubility of KNO3, for example. I have a reference at home that gives an approximate solubility of 36 g KNO3 in 100 mL water @ 25 degrees C, The value at 82 degrees C will be different but we would say the solution was supersaturated if the question was for 25 degrees C.
As an example, and using the solubility at 25 degrees C as 36 g KNO3/100 mL, a soln would be classified as follows:
1 g/100 mL would be unsaturated becasue it COULD dissolve more.

36 g/100 mL would be saturated since that is the limit of its solubility. Another crystal added to that solution would simply float to the bottom of the flask and not dissolve.

If by some hook or crook we dissolved 50 g KNO3/100 mL water at 25 degrees C., we would call it supersaturated because the solvent has dissolved MORE THAN what is required for a saturated solution; thus the name supersaturated. (You may wonder how one does that. For some salts we could raise the temperature to near boiling, dissolve more than would be required for a saturated solution at 25 C., then let the solution cool slowly and without agitation. Some salts will not precipitate the excess amount of salt; thus we have a supersaturated solution. I hope this helps.

To determine if a solution is saturated, supersaturated, or unsaturated, you need to compare the actual concentration of a solute in the solution with its maximum solubility at a given temperature.

1. KNO3 90g/100g at 82°C:
First, you need to find the solubility of KNO3 at 82°C. This information can be obtained from a reference book or an online database. Let's assume that the solubility of KNO3 at 82°C is 100g/100g of water. Since the solution contains 90g of KNO3, which is less than the solubility, it is unsaturated.

2. NaCl 36g/100g at 23°C:
Similarly, you need to find the solubility of NaCl at 23°C. Let's assume that the solubility of NaCl at 23°C is 40g/100g of water. Since the solution contains 36g of NaCl, which is less than the solubility, it is unsaturated.

3. KCl 35g/100g at 18°C:
Again, find the solubility of KCl at 18°C. Let's assume that the solubility of KCl at 18°C is 30g/100g of water. Since the solution contains 35g of KCl, which is greater than the solubility, it is supersaturated.

4. NaNO3 90g/100g at 28°C:
Lastly, find the solubility of NaNO3 at 28°C. Let's assume that the solubility of NaNO3 at 28°C is 80g/100g of water. Since the solution contains 90g of NaNO3, which is greater than the solubility, it is supersaturated.

Remember, the solubility values provided here are hypothetical examples. It is essential to consult reliable sources for accurate and specific solubility data for each substance at the given temperature.

To determine if a solution is saturated, supersaturated, or unsaturated, you need to compare the given solubility information with the actual concentration of the solute in the solution.

1. KNO3 90g/100g at 82°C:
To determine the classification, you need to compare the given solubility information with the actual concentration. If the solubility of KNO3 at 82°C is higher than 90g/100g, the solution is unsaturated. If the solubility is exactly 90g/100g, the solution is saturated. If the solubility is lower than 90g/100g, the solution is supersaturated. You'll need to consult a reference or specific solubility data for KNO3 at 82°C to determine its classification.

2. NaCl 36g/100g at 23°C:
Using the same approach, if the solubility of NaCl at 23°C is higher than 36g/100g, the solution is unsaturated. If the solubility is exactly 36g/100g, the solution is saturated. If the solubility is lower than 36g/100g, the solution is supersaturated.

3. KCl 35g/100g at 18°C:
Similar to the previous examples, compare the given solubility information with the actual concentration. If the solubility of KCl at 18°C is higher than 35g/100g, the solution is unsaturated. If the solubility is exactly 35g/100g, the solution is saturated. If the solubility is lower than 35g/100g, the solution is supersaturated.

4. NaNO3 90g/100g at 28°C:
Again, compare the given solubility information with the actual concentration. If the solubility of NaNO3 at 28°C is higher than 90g/100g, the solution is unsaturated. If the solubility is exactly 90g/100g, the solution is saturated. If the solubility is lower than 90g/100g, the solution is supersaturated.

Remember, to determine the exact classification for each solution, you'll need to refer to solubility data specific to the given temperature.