Experiment 4B

Variation in volume of extraction solvent: compound X is dissolved in 20.0 mL of solvent B. Assuming a partition coefficient of PX,AB of 5.0, calculate the percentage of X that remains in solvent B if it is extracted the following volumes of solvent A:   1.0 mL 10.0 mL 20.0 mL 100.0 mL

An unknown substance "A" was allowed to partition between a mixture of 150 mL water and 80 mL benzene. After titration, you found that 0.75 moles of "A" was dissolved in the water while 0.60 moles dissolved in benzene. Calculate for the partition coefficient of substance "A". What can you infer about the nature of substance "A" based on the value of the partition coefficient?

You add 1 mL of sample and collect 1 mL fractions from a column with a volume of 20 mL where the beads take up 60% of the column and the protein of interest has a partition coefficient of 0.4. What fraction do you want to keep?

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6. ( If the solubility of solute Z is 1.0 g/60 mL in diethyl ether and is 1.0 g/1110 mL in water. a) Determine the partition coefficient for the solute Z in these two solvents. b) If 60 mg of the solute Z were dissolved in 100 mL of water, how much ether would be required to extract 90% of solute Z in a single extraction. c) What percent of the A would be extracted from the aqueous solution in (b) by two 50 mL portions of ether?

Partition coefficients (Kow = organic solvent concentration/aqueous concentration, usually reported as log Kow) are important for determining how efficiently organic compounds can be extracted from aqueous solutions. For example, consider the two substances below. Which will be more soluble in water? Hexamethylbenzene (log Kow = 6.41) O Diethyl ether (log Kow = 0.83)

The partition coefficient(k)of a substance between petroleum ether and water is 6. A substance of mass 12 g is dissolved in 50 mL of water. Calculate the total mass of sample that can be extracted into 40 mL of ether if the ether is used in two 20 mL portions.

Your group was allocated an unknown substance X and instructed to measure its partition coefficient between an organic solvent and water as part of a lab activity. 4 grams of X are dissolved and shaken in a combination of 130 mL benzene and 100 mL water. Finally, your group identified 0.5 g of X in the benzene layer. Calculate the partition coefficient using the information supplied. What can you tell about substance X's chemical composition?

Need HELP ASAP Calculate the partition coefficient Kd of X in hexane. Answer in 4 significant figures. Calculate the partition coefficient Kd of X in chloroform. Answer in 4 significant figures.

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700 mg of Antimony (Sb) was dissolved in 100 mL of HCl, an equal volume of isopropyl ether was added, and the system thoroughly shaken. The layers were separated; and the ether, evaporated. The residue was found to contain 685 mg of Antimony.  What is the distribution ratio? What is the partition coefficient?

substance of mass 10 g is dissolved in 50 mL of water. Calculate the total mass of sample that can be extracted into 40 mL of ether, if the ether is used in two 20 mL portions .The partition coefficient(k)of the substance between petroleum ether and water is give 4

c) diethyl ether. After separating the layers, 240 mg of cyclohexanol are recovered from the diethyl ether layer. You approximate that the remaining 10 mg of cyclohexanol must have been dissolved in the aqueous layer. Calculate the partition coefficient. Show work. 250 mg of 1-phenylcyclohexanol are dissolved in a combination of 10 mL of water and 20 mL of

The partition coefficient, Kp, at 25°C (i.e., room temperature) for compound A is 9.71 (for water and benzene). Starting with a solution of 16.6 g of compound A in 110 mL of water, what is the total percent of compound A that is extracted into the benzene after two successive extractions of 65.0 mL benzene each? [Enter a value with 3 sig figs and do not include the % sign]

Use your knowledge in analytical processes to systematically outline a protocol you will follow to process adulterated palm oil to gain qualitative and quantitative information spectroscopically about any added toxic dye. Explain also the basis for your protocol of choice.

If the solubility of a drug is 3.8g/L and in chloroform 226g/L calculate its partition coefficient to 1 decimal place

A solution of 3g organic compound X in 200ml of water was extracted with 200 ml of ethyl ether. At equilibrium the concentration of Xin the two phases was ; 2.6g/100ml of ethyl ether ; 0.8g/100 ml of water. Calculate the partition coefficient, Kd, for compound X in the system. Show your calculations and What percentage of the original sample of X was extracted? Show your calculations.

A liquid/liquid extraction is performed to separate the following drug from a urine sample: Ibuprofen. The drug has a pka of 4.43+0.03 and an n-octanol/water partition coefficient of 11.7 at pH 7.4. 1. Assume you have a 20nM concentration of the drug in urine. You perform a liquid/liquid extraction of 20mL of urine with 10 mL of octanol at pH 7.4. What is your percent recovery? 2. Would your recovery be higher or lower at pH 2.0? 3. Explain what steps you would use to extract the drug by solid phase extraction. 7:55 PM V

2) Assume you are decaffeinating your coffee by extracting the caffeine out with dichloromethane. Your particular brand of coffee contains 100 mg of caffeine in a 200 mL cup of water. The partition coefficient of caffeine in dichloromethane/water is 8.0 (it is more soluble in the dichloromethane).Answer the following questions about how much caffeine would still be in the 200 mL of water based on two different approaches. You should solve this algebraically. If you use an equation found on the internet, you will need to show how it was derived to receive credit.a) How much caffeine would remain in the water after extracting once with 200 mL of dichloromethane? Show your work.b) How much caffeine would remain in the water after extracting twice, each time with 100 mL of dichloromethane? Show your work.

Qd 170.