Module 1 - Solvent Extraction and Partition Coefficient Part A

Ethyl heptanoate (EH), a food aroma compound, was added to water and allowed to come to equilibrium with a known volume of air and results showed that its partition coefficient, [EHair]/[EHwater] is equal to 1.8 x 10-2. In the same experiment with oil in place of water, its partition coefficient, [EHair]/[EHoi] is found to be lower at 6.0 x 10-6. Account for the difference between the two values.

how can i calculate part a

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.

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?

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)

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.

What is the partition Coefficient of phenazopyridine? With illustration

If the solubility of a drug is 3.8 g/L and in chloroform 224.9 g/L calculate its partition coefficient.

Define a molar extinction coefficient and briefly describe how it is measured.

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

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

You left a bowl of refried beans in the refrigerator too long. One day your roommate opens the fridge and it smells like rotten egg (due to generated hydrogen sulfide, H2S). You immediately run to the store to purchase activated charcoal to remove the odor. From a quick search online you learn that the linear partitioning coefficient is 30 m/kg. Assuming that the refrigerator volume is 0.5 m?, the initial odor concentration is 3.2 ug/m³, and the final concentration is 0.3 ug/m3 , calculate the minimum mass of adsorbent (in g) you need to purchase. Enter your final answer with 2 decimal places. It is proposed to add activated carbon to treat a storm stream with a pollutant concentration of 5.1 mg/L. If the treatment plant has only 22 kg of activated carbon, how many liters of waste stream can be treated to achieve an equilibrium effluent concentration of 2.0 mg/L? Lab tests show that Freundlich isotherm coefficients for the activated carbon and the pollutant are K, 0.09 L/kg and n = 2.8…

It is found that up to 0.0110 g of SrF2 dissolves in 100 mL of aqueous solution at a certain temperature. Determine the value of Ksp for SRF2. 1 2 NEXT > Based on the given values, fill in the ICE table to determine concentrations of all reactants and products. SFF2(s) Sr**(aq) 2 F (aq) + Initial (M) Change (M) Equilibrium (M) 5 RESET 0.0110 8.76 x 10-5 8.76 x 10-4 1.75 x 10-4 1.75 x 103 -0.0110 -8.76 x 10-5 -8.76 x 10-4 -1.75 x 10-4 -1.75 x 103 +x +2x -2х -X 8.76 x 10-5 + x 8.76 x 10-5 1.75 x 10-4 + 2x 1.75 x 10-4 - 2x

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?

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.

Experimentally measured adsorption isotherms often deviate from the Langmuir model. Explain what causes these deviations, and why the Langmuir model generally describes chemisorption better than physisorption.

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2) Consider the following reaction and associated rate law: X (g) + Y(g) → Z Rate = k[X] [Y] b Use the data in Table 1 in the following problems. Table 1 Reaction Data [X]。 (M) [Y]。 (M) Rate (M/s) 0.882 0.217 283. 07 0.882 0.451 624. 47 0.882 0.572 820.57 0.882 0.882 1308. 22 0.228 0.882 124.96 0.442 0.882 382. 56 0.67 0.882 804. 48

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?

A 78 mg sample of an organic compound (molar mass = 84.0 g/mol) is partitioned between 2.00 mL of water and 2.00 mL of methylene chloride. Separation and processing of the organic phase results in the isolation of 58 mg of the organic compound. Calculate the partition coefficient for the compound between methylene chloride and water (Kpmethylene chloride/water). Your answer should reflect the proper number of significant figures.

R. Atkinson (J. Phys. Chem. Ref. Data 26, 215 (1997)) has reviewed a large set of rate constants relevant to the atmospheric chemistry of volatile organic compounds. The recommended rate constant for the bimolecular reaction of O2 with an alkyl radical R at 298 K is 4.7 × 109 dm3 mol−1 s−1for R = C2H5 and 8.4 × 109 dm3 mol−1 s−1 for R = cyclohexyl. Assuming no energy barrier, compute the steric factor, P, for each reaction. Hint: Obtain collision diameters from collision cross-sections of similar molecules in the Resource section.

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

In a FRET experiment designed to monitor conformational changes in T4 lysozyme, the fluorescence intensity fluctuates between 5000 and 10,000 counts per second. Assuming that 7500 counts represents a FRET efficiency of 0.6, what is the change in FRET pair separation distance during the reaction? For the tetramethylrhodamine-texas red FRET pair employed ro = 50. Å. Express your answer to two significant figures and include the appropriate units. HÀ ? Ar = Value Units

The partition coefficient K for a compound between dichloromethane and water is determined to be 56 : 1 (K=56). If 10.0 mg of the compound is dissolved in 50.0 mL of water and this solution extracted with 25.0 mL of dichloromethane, how many mg of the compound will remain in the water layer following the extraction procedure? Show you calculations