To Sheryl: polarity

The exact question is: Benzyl alcohol (bp 205 degree C) was selected by a student to crystallize fluorenol (mp 153-154 degrees C) because the solubility characteristics of this solvent are appropriate. However, this solvent is not a good choice. Explain.

So the melting point looks okay and both would seem to be nonpolar, according to your researches. What else could it be?

I talked to my friend at lunch. He has a Ph. D. in organic chemistry. The OH on the fluorene (to become fluorenol) is somewhat acidic making it somewhat polar. But the REAL problem is that benzyl alcohol (which isn't very polar either)is just too good a solvent; i.e. the same reasoning we went through on the biphenyl/benzene crystallization. The fluorenol is so soluble in benzyl alcohol that very little can be removed after solution so it is a poor solvent for purposes of recrystallization. I hope this information is useful. BTW, I thought some more about the Buchner funnel/saturated solution question we were discussing. We know, of course, that cooling will take place and that some of the solute probably will ppt which makes solute appear as a solid on th funnel as well as in the liquid that goes through the funnel. Therefore, a good separation is not obtained BETWEEN THE SOLUTE AND THE SOLVENT. But that may not be the real question. Why did we filter the saturated solution in the first place. If because we want to seaparate some solid impurities from the solute in the saturated solution, we will have the solid impurities along with some of the crystallized solute in the Buchner funnel. Again, if the solute is what we are interesting in collecting, then the yield suffers because some of the product has been removed from the solvent and is mixed in with the solid impurities.

Thanks for the extra effort. Just got back from lab.

Hope you had a nice lunch with your friend.


  1. 👍
  2. 👎
  3. 👁
  1. No, it's because the BP (205C) is too high for fluorenol's MP. So you boil your solution and it's still all dissolved, but you start cooling it and instead of the fluorenol crystallizing it will start "oiling" out, as in becoming a miscible liquid in the benzyl alcohol, so you won't get crystals.

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Statistics

    The body temperatures of adults are normally distributed with a mean of 98.6 degree F and a standard deviation of 0.60 degree F. If 36 adults are randomly selected, find the probability that their mean body temperature is greater

  2. physics

    Suppose the amount of heat removed when 3.0kg of water freezes at 0 degree C were removed from ethyl alcohol and its freezing/melting point of -114 degree C. How many kilograms of ethyl alcohol would freeze? PLEASE GIVE ME SOME

  3. Mental Health Diagnosis and assessment

    Hello I am not sure about my answers. Can someone help me? Jose is a Latino client who presents with occupational difficulties. He was laid off from a construction job 8 months ago and has been unable to find work. Ever since he

  4. Polarity

    Benzyl alcohol is not a good sovent with which to crystallize fluorenol. The melting point looks okay so I'm assuming that polarity is the problem. Benzyl alcohol looks polar to me because it has an OH but it is only partly

  1. Statistics

    A class consists of 23 women and 83 men. If a student is randomly selected, what is the probability that the student is a woman?

  2. statistics

    Let x be the number of courses for which a randomly selected student at a certain university is registered. The probability distribution of x appears in the table shown below: x 1 2 3 4 5 6 7 p(x) .04 .05 .08 .26 .39 .16 .02 (a)

  3. AP Chem

    A student conducts an experiments to determine the enthalpy of neutralization for phosphoric acid reacting with sodium hydroxide. The student combines 25.0 mL of equimolar solutions of acid and base, both having an initial

  4. fin. am I correct?

    13. Healthy Foods, Inc. sells 50-pound bags of grapes to the military for $10 a bag. The fixed costs of this operation are $80,000, while the variable costs of the Grapes are $.10 per pound. a. What is the break-even point in

  1. Rf values

    Question: Consider a sample that is a mixture composed of biphenyl, benzoic acid and benzyl alcohol. The sample is spotted on a TLC plate and developed in a dichloromethane-cyclobutane solvent mixture. Predict the relative Rf

  2. Mathematics

    Among 500 freshmen pursuing a business degree at a university, 313 are enrolled in an economics course, 205 are enrolled in a mathematics course, and 153 are enrolled in both an economics and a mathematics course. What is the

  3. Health

    avoiding situations where alcohol is present will help you stick to your decision to be alcohol free. true or false? Drinking on an empty stomach can increase Blood Alcohol concentration (BAC) TRUE or false? Alcohol decreases a

  4. statistics

    One student is selected at random from a student body. Suppose the probability that this student is female is 0.5 and the probability that this student works part time is 0.6. Are the two events "female" and "working" mutually

You can view more similar questions or ask a new question.