Consider the crystallization of sulfanilamide from 95% ethyl alcohol. If impure sulfanilamide is dissolved in the minimum amount of 95% ethyl alcohol at 40°C rather than 78°C (the boiling point of ethyl alcohol), how would this affect the percent recovery of pure sulfanilamide? Explain your answer.

it would lower the percent recovery since the impure sulfanilamide is not able to fully dissolve and crystallize as it slowly cools

Well, I must say, talking about the crystallization of sulfanilamide really brings out the "sulfana-maniac" in me! Now, let's dive into your question.

When it comes to the crystallization process, temperature plays a critical role. If you dissolve impure sulfanilamide in the minimum amount of 95% ethyl alcohol at a lower temperature, such as 40°C, instead of the boiling point of ethyl alcohol at 78°C, it will affect the percent recovery of pure sulfanilamide.

You see, temperature affects the solubility of compounds. Generally, as temperature increases, the solubility of most compounds increases as well. But in this specific case, sulfanilamide, being a sneaky fellow, decides to do the opposite. It's an exception to the "rule of thumb."

At lower temperatures, the solubility of sulfanilamide in 95% ethyl alcohol is significantly lower compared to higher temperatures. So, by dissolving it at 40°C instead of 78°C, you're essentially giving those impurities a golden ticket to stay in solution while sulfanilamide prefers to take a nap and crystallize out.

This means that at the lower temperature, a higher percentage of pure sulfanilamide will crystallize out of the solution, resulting in a better percent recovery of pure sulfanilamide. So, in a nutshell, lowering the temperature to 40°C would increase the percent recovery of pure sulfanilamide. Isn't science a fascinating puzzle?

I hope I was clear enough without getting too "crystal-clear." Let me know if there's anything else I can help you with!

When sulfanilamide is crystallized from a solvent, such as 95% ethyl alcohol, it forms pure crystals while leaving behind impurities in the solution. The solubility of a compound typically decreases with decreasing temperature. Therefore, if impure sulfanilamide is dissolved in the minimum amount of 95% ethyl alcohol at 40°C instead of 78°C, there are a few factors to consider that may affect the percent recovery of pure sulfanilamide:

1. Solubility: At 40°C, the solubility of sulfanilamide in 95% ethyl alcohol is lower compared to 78°C. This means that a smaller amount of sulfanilamide can be dissolved in the 95% ethyl alcohol solution at 40°C. Consequently, the crystallization process will yield fewer sulfanilamide crystals, potentially leading to a lower percent recovery of pure sulfanilamide.

2. Impurity Solubility: The solubility of impurities in the solution may be affected differently by the lower temperature. Some impurities that were soluble at 78°C may become less soluble at 40°C, resulting in their precipitation along with the sulfanilamide crystals. This would lead to a higher percent recovery of pure sulfanilamide.

3. Crystal Quality: Lowering the temperature may result in slower crystal growth. Slower crystal growth can allow impurities to be trapped within the crystal lattice, decreasing the overall purity of the crystals obtained. This would also lead to a lower percent recovery of pure sulfanilamide.

Overall, the lower temperature of 40°C may affect the percent recovery of pure sulfanilamide by reducing the solubility of sulfanilamide, potentially impacting the solubility of impurities differently, and influencing the quality of the crystals formed.

To understand how the change in temperature would affect the percent recovery of pure sulfanilamide during crystallization, we need to consider the solubility of sulfanilamide in 95% ethyl alcohol at different temperatures.

First, let's understand the concept of solubility. Solubility refers to the maximum amount of solute (in this case, sulfanilamide) that can dissolve in a given amount of solvent (ethyl alcohol) at a specific temperature. Generally, solubility increases with temperature for most solutes.

In the given scenario, we have impure sulfanilamide dissolved in the minimum amount of 95% ethyl alcohol at 40°C, rather than the boiling point of ethyl alcohol, 78°C.

At 40°C, the solubility of sulfanilamide in 95% ethyl alcohol is lower compared to the solubility at 78°C. This means that at 40°C, less sulfanilamide can dissolve in the same amount of alcohol compared to 78°C.

Now, let's consider the effect on the percent recovery of pure sulfanilamide. In the crystallization process, as the temperature decreases, the solute (sulfanilamide) becomes less soluble in the solvent (ethyl alcohol). This leads to the formation of crystals as the solute starts to come out of the solution.

Since the solution is already saturated with impure sulfanilamide at 40°C, reducing the temperature further will cause more sulfanilamide to precipitate out as crystals. The impurities, on the other hand, will remain dissolved or have lower solubility and be left behind in the solution.

As a result, when the solution is cooled and the crystals are collected, the percent recovery of pure sulfanilamide will be higher at 40°C compared to 78°C. This is because more of the impurities will remain in the solution while most of the pure sulfanilamide will form crystals.

Therefore, the change in temperature from 78°C to 40°C during the crystallization of sulfanilamide from 95% ethyl alcohol will likely increase the percent recovery of pure sulfanilamide.