Module 2 Lab Report

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?

If the concentration in a bulk solution adjacent to a fibrous medium is at a concentration cA = 1mM, and partition coefficient of K = 0.7, what is the concentration in the %3D leading edge of the fibrous medium? the answer has units of mM (canvas does not allow you to enter units or display the answer with units.) your answer mM

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?

Chemistry A 50ml aliquot of a 0.1 M solution of a neutral drug was extracted with 2 x 5 ml ethyl acetate. The drug concentration in the combined organic layers was found to be 0.36 M. Calculate the partition coefficient for this drug under these conditions.

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)

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The partition coefficient for caffeine between dichloromethane and water is 4.6.  Assume that a 100 mL tea solution (in water) contained 100 mg of caffeine.  What is the theoretical yield of caffeine in the methylene chloride if you extract with one 100 mL portion of methylene chloride?

Naphthalene has a log Kow of 3.33. Estimate its soil-water partition coefficient normalized to organic carbon and the 95 percent confidence interval of your estimate.

If the partition coefficient of CBN from water into ethanol is 4, what fraction q of the CBN would remain in a 424 mL aqueous sample if it was extracted with 69 mL of ethanol twice?

Acetone has a partition coefficient of 13 while DCM has a partition coefficient of 4.6. Why is DCM used for the extraction of caffeine from Black teabags?

At 25 °C, the octanol-water equilibrium partition coefficient KOW of Compound X is 150,000 and its water-gas phase equilibrium partition coefficient KWA is 5000. Estimate the octanol-gas phase equilibrium partition coefficient KOA of Compound X.

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.

The octanol - water aqueous buffer partition coefficients (P) for a drug used to treat glaucoma were obtained experimentally at various temperatures (T) and pH values. The results are presented in the following table: pH=7.0 0.72 0.84 pH=6.25 pH=7.25 T= 27 C 0.24 0.89 T= 30 C 0.31 1.06 T= 40 C 1.23 1.49 27.4 mg of this drug were dissolved in 100 mL of buffered water (pH=7.0; T=30) and then partitioned with octanol portions of 37.1 mL. Calculate how many mg of drug will remain in water after in the first extraction (Fill in ONLY numbers approximated to the 2nd decimal place) Answer: 19.01

The partition coefficient of iodine between CCl4 and water is Сcc14/CH₂0 = K = 85, where the C₁ represent the concentration in mol/L of iodine in the solvent. (a) If you want to extract 90% of the iodine from 100 mL of an aqueous iodine solution in a single extraction, Calculate the volume of carbon tetrachloride needed. (b) If you want to extract 90% of the iodine from 100 mL of an aqueous iodine solution in two extractions of equal volumes, calculate the volume of carbon tetrachloride needed in each. (c) If ß is the fraction of iodine remaining in the aqueous solution after n extractions with equal volumes of CC14, show that as n→ ∞, the total required volume of CCl4 per unit volume of water for each extraction is given by: Remember that: ln(1+x) ≈ x 2 VCC4,tot VH₂0 + 몰.... 3 In 3 K

6. To purify water which has iodine in it, one can use extraction with CCI4. The equation can be written as I2 (aq) S I2 (CCL). What is the partition coefficient? 1 b. K =. K=[1,L, a. K = с. К3. d. 1 %3D е. 7. Consider the unbalanced chemical equation CaCO; + H3PO4 smallest integer coefficients, the coefficient for CO, is Ca3(PO4) 2 + CO2 + H2O. When the reaction is balanced with a. 1 b. 3 с. 5 d. 7 e. none of these

Two compounds with partition coefficients of 15 and 18 are to be separated on a column with VSVM=0.30VSVM=0.30.  Calculate the number of theoretical plates needed to produce a resolution of 1.8. Do not worry about significant figures of your final answer.

When a solution of 1.00 g of X in 100 cm³ of water was shaken with 10 cm3 of ether, 0.80 g of X was transferred to the ether layer. Calculate the partition coefficient of X .between ether and water

What is the partition Coefficient of phenazopyridine? With illustration

What is the molar extinction coefficient (e) for o-nitrophenol at lmax?  Explain how you arrived at this value.

Suppose that the acid HA (with dissociation constant Ka) is partitioned between aqueous phase 1 and organic phase 2. Calling the partition coefficient K for HA and assuming that A is not soluble in the organic phase, show that the distribution coefficient is given by: D= K· [H+ ] / [H+ ] + Ka = K · aHA

The active ingredient in Tylenol is acetaminophen. Suppose you had a mixture of acetaminophen and sodium chloride and wanted to separate it. Acetaminophen is soluble in ethyl acetate, CH3COOEt, and slightly soluble in water. Sodium chloride, on the other hand, is water soluble. Let’s assume that the partition coefficient for acetaminophen is KD = 8 between ethyl acetate and water mixture. If we start with a salt acetaminophen mixture that contains 10 g of acetaminophen dissolved in 100 mL of water, how much acetaminophen can we extract with two extractions of ethyl acetate 20 mL each?Do each extraction separately. Calculate how much do you extract with one extraction first. Then consider how much remains in the aqueous layer and extract again.