4. Describe the relationship between molecular charge and solubility in organic or aqueous media. Why is this relationship important for understanding drug absorption?

4. TLC is still useful in the lab but is being replaced by automated chromatographic methods. For example, TLC, FPLC, and HPLC are now automated processes, and computers can control various parameters, such as flow rate, blends of solvent mixtures, etc. Can you think of how the ability to manipulate the parameters of these automated chromatographic methods (sample size, column plate length, flow rate, solvent gradients, etc.) might accentuate or improve an investigator's ability to separate amino acids or other biomolecules?

Ba 06. in the column chromatography of spinach extract Could you potentially see the usefulness of this method in a field outside of the organic chemistry lab? Explain why or why not.

4. A protein solution is prepared by dissolving 350 µg of protein in 200 µL of water. A 150 μL sample of this solution is diluted to a total volume of 4.5 mL. How many mg of protein will be in a 2 mL sample of the diluted protein solution? Space to show your workings:

2. Why would you expect to see no violet color when free amino acids (no peptide bonds) are mixed with Biuret reagent?

II. Lipids from an organic sample are extracted separately by column chromatography using the ff eluants: 1st eluant - chloroform: methanol: water (6:3:1) 2nd eluant - methanol: chloroform (9:1)3rd eluant – petroleum ether: ethyl ether (1:1) Test results for each eluate are tabulated below. Identify the possible lipid present in each eluate. Based on the results above, _________________ 1. _________________ 2. _________________ 3. _________________ 4. _________________ 5. answer the following questions: What visible positive result for test reagent no. 5?Give the name of chemical characterization test for test reagent no. 3?What class of lipids will give a visible positive result on the test mentioned in question no. 2?Give the chemical name of the product formed after giving a positive result for test reagent no. 1?Test reagent no. 1 is used to test for what organic compound?

Select all that apply: Hydrogen peroxide and other gases affect the structure of O Proteins O DNA Cell membranes O Cell walls