1. When doing a recrystallization, what observations wouldprompt you to perform
ID: 683499 • Letter: 1
Question
1. When doing a recrystallization, what observations wouldprompt you to perform a hot filtration? 2. What problems might arise if a hot solution is filtered byvaccum foltration? 3. What is meant when aniline is referred to as the "limitingreagent" in the reaction with acetic anhydried? 4. Under what circumstances would you use mized solvents in arecrystallization? 5. Why do you we keep tje volume of the rinses small inthe recrystallization procedure? 1. When doing a recrystallization, what observations wouldprompt you to perform a hot filtration? 2. What problems might arise if a hot solution is filtered byvaccum foltration? 3. What is meant when aniline is referred to as the "limitingreagent" in the reaction with acetic anhydried? 4. Under what circumstances would you use mized solvents in arecrystallization? 5. Why do you we keep tje volume of the rinses small inthe recrystallization procedure?Explanation / Answer
2. In a hot solution, vaccuum filtration will result in arapid decrease of pressure resulting in expansion in gaseous state.This can lead to all sorts of problems, especially if you havesomething volatile, such as, well explosions.
3. A limiting reagent is one that limits the reaction. Whenstoicometrically reacted, it is used up faster than other reagents,which are in turn, in excess.
4. Many times, finding an appropriate solvent to dissolve thecompound when it is hot, but not when it is cold, can be difficult.In that case you do a mixed recrystallization.
5. By thier very nature, the rinses should not dissolve thecrystal, but in large excess they can still dissolve it in minutequantities. Also, you must then remove any excess solution. A thirdproblem may be some of the crystal being washed away. Basically,small rinses mean a higer yield, less waste, and a more efficientprocess overall.
For future reference, questions with this many parts should besplit up. This might be in violation of policy. Also people aremore willing to answer parts of it atleast.
Best of luck and please rate!!!
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.