Chemistry

posted by .

I am about to do an extraction experiment, and needed help with a question to improve my understanding. Any help appreciated.

1. You have 150 ml of a solution of benzoic acid in water estimated to contain about 5g of the acid. The distribution coeffcient of benzoic acid in benzene and water is approx. 10. Calculate the amount of acid that would be left in the water solution after three 50 ml extractions with benzene. SO the same calculation using one 150ml extraction with benzene to determine which method is more efficient.


Also I was wondering why three small extractions are more efficient than one large extraction, and how can this be proven?

  • Chemistry -

    a. The main reason that three extractions are more efficient than one large one is that the first extraction takes out a portion, the second extraction STARTS with less than the first and the third extraction starts with even less. It's the same process as transferring a solution quantitatively from one beaker to another. You can fill the beaker with water and pour into the other beaker with one transfer OR you can wash with four or five 5-mL portions and pour each rinse into the other beaker. You will get quantitative transfer (meaning all of it) with four or five SMALL rinses but you will not get quantitative transfer with just one large (or small) rinse.
    b. The way you prove this is to do it.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Organic Chemistry - Extraction

    You have 100 mL of a solution of benzoic acid in water; the amount of benzoic acid in the solution is estimated to be about 0.30 g. The distribution coefficient of benzoic acid in diethyl ether and water is approximately 10. Calculate …
  2. Chemistry

    You have 150 ml of a solution of benzoic acid in water estimated to contain about 5 g of acid. The distribution coefficient of benzoic acid in benzene and water is approx 10. Calculate the amount of acid that would be left in the water …
  3. Chemistry

    You have 150 ml of a solution of benzoic acid in water estimated to contain about 5 g of acid. The distribution coefficient of benzoic acid in benzene and water is approx 10. Calculate the amount of acid that would be left in the water …
  4. Chemistry

    You have a solution that contains 5.0 grams of oxalic acid dissolved in 150 mL of water. This solution is placed in a seqparatory funnel, and the 100 mL of diethyl ether is added to the separatory funnel and an extraction is performed. …
  5. Ochem

    A student needed to determine the percent composition of a mixture that contained fluorene and benzoic acid. The student took 283 mg of the mixture and used the extraction method to separate the components. Then both compounds were …
  6. Chemistry

    Assume the solubility of benzoic acid in ice-cold water is 1.70 g/L and the solubility of benzoic acid in hot water is 68.0 g/L. Calculate the minimum volume of water (in mL) needed to recrystallize 0.350 g of benzoic acid.
  7. chem

    If 20.5 mL of a 5.256 M solution of benzoic acid is used in an experiment similar to experiment 4, how many grams of benzoic acid is in the starting solution?
  8. Chemistry

    Okay, I have some confusion on a lab question for chemistry. The question was if you were preforming a microscale extraction of a 0.2 g of benzoic acid/fluorenone mixture (About 6 mL of dichloromethane and 2 mL of NaOH were added through …
  9. Chemistry (organic)

    You have a solution that contains 5.0 g of oxalic acid dissolved in 150 mL of water. This solution is placed in a separatory funnel, and then 100 mL of diethyl either is added to the separatory funnel and an extraction is performed …
  10. Chemistry

    References Chapter 17: EOC Assume you dissolve 0.178 g of the weak acid benzoic acid, , in enough water to make mL of solution and then titrate the solution with 0.187 M . ( for benzoic acid = .) What was the pH of the original benzoic …

More Similar Questions