The solubility of a certain compound in ice-cold water is 0.22g in 100mL. Its solubility in hot water is 4.35g in 100mL What is the best possible percent recovery we can expect for the re-crystallization of this compound in water?

I worked this last night for another student and thought too little information was given. Here is another take on it.

If we take a 4.35 g sample, it will require 100 mL of hot water to dissolve it. When it crystallizes in ice cold water, we lose 0.22 g of it. Therefore, we can recover 4.35-0.22 = 4.13g.
%recovery = (4.13/4.35)*100 = x

Thank you so much drbob! Your explanation make sense! :D

To calculate the best possible percent recovery for re-crystallization, we need to compare the solubility of the compound in ice-cold water with its solubility in hot water.

The initial amount of the compound in ice-cold water is given as 0.22g in 100mL, and the solubility in hot water is given as 4.35g in 100mL.

Step 1: Calculate the ratio of the compound's solubility in hot water to its solubility in ice-cold water:

Ratio = Solubility in Hot Water / Solubility in Ice-Cold Water

Ratio = 4.35g / 0.22g

Ratio ≈ 19.77

Step 2: Calculate the percent recovery:

Percent Recovery = (Ratio / (1 + Ratio)) * 100

Percent Recovery = (19.77 / (1 + 19.77)) * 100

Percent Recovery ≈ 95.23%

Thus, the best possible percent recovery we can expect for the re-crystallization of this compound in water is approximately 95.23%.

To determine the best possible percent recovery for the re-crystallization of the compound, we need to compare the solubility in ice-cold water and hot water.

First, we need to determine the amount of the compound that can be dissolved in each solvent:

In ice-cold water:
Solubility = 0.22 g/100 mL

In hot water:
Solubility = 4.35 g/100 mL

To obtain the maximum recovery, we want to completely dissolve the compound in hot water and then re-crystallize it in ice-cold water. This way, all of the compound will be recovered.

Since the solubility in hot water is higher (4.35 g/100 mL), we can dissolve a larger amount of the compound. Therefore, the maximum amount we can recover is 4.35 g.

To calculate the percent recovery, we need to compare the amount recovered to the initial amount used.

Assuming we start with 100 g of the compound, the percent recovery is given by:

Percent recovery = (Amount recovered / Initial amount) x 100
= (4.35 g / 100 g) x 100
= 4.35%

So, the best possible percent recovery we can expect for the re-crystallization of this compound in water is 4.35%.