3. If acetic acid is not added to the TLC solvent, what effect would you predict...
3. If the TLC plate development had stopped before the solvent front reached the top of the TLC plate (i.e. maybe it reached the middle of the TLC plate when it was stopped, instead): a) Would the Rf values have been affected? If so, how? If not, why not? Give a numerical example to support your answer. b) Would the size of the spots have been affected? If so, how? If not, why not? (Hint: think about the diffusion of...
When using normal phase TLC for the separation of benzoic acid and salicylic acid, which compound would produce a larger Rf value and why? What would happen to the Rf values if the solvent polarity were increased?
The reaction was: 4-aminophenol + acetic anhydride + water (solvent) --> acetaminophen + acetic acid In this experiment, we characterize the products only by obtaining an experimental melting point. How could you use TLC to confirm that (i) your isolated product is pure, and (ii) your product is acetaminophen? [2 marks]
Possible Quiz Questions 1 What two methods of visualizing spots on a TLC plate will you use in this Give two reasons why would you predict that the elution solvents (hexanes or acetate) would not be visible under UV visualization? week's lab? ethyl 2. Define R 3. Calculate the R of the spot on the following TLC plate. 4. Which compound in each pair is predicted to have the higher Ri? a. CH3CH2CH2CH2OH and CH3CH2CH2CH28r b. CH3CH2CH2CH2OH and CH3CH2CH2CH2CH2CH2CH3 c....
3) What two methods of visualizing spots on the TLC plate will you use in this lab? Why would you predict that the elution solvents (hexanes or ethyl acetate) would not be visible under UV visualization?
If you added too much acetic acid to the milk solution , what would happen to the lactose? Please, draw the products of the reaction that would occur. Thank you!
4)If you took a TLC of the would happen if you used the first eluting solvent as the developing solvent? What if you used the second eluting solvent? Draw a picture of each TLC plate as you think it would look original solution containing both β-carotene and chlorophyl, what 2 pts) β-carotene and chlorophyll in 30:70 acetone:pet ether β-carotene and chlorophyll in ethanol: Answer the following questions about conjugated double bonds and light absorption. d double bonds are necessary for...
what effect would the following have on the reaction between salicylic acid and acetic anhydride? Support your reasoning by drawing the mechanism for the reaction and incorporating them in the mechanism. 1. anhydride sodium acetate 2.pyridine 3. boron trifluoride and 4. concentrated sulfuric acid
How many peaks would you predict would appear in the Carbon-13 NMR spectrum for acetic acid? Please label all carbons in your structure. Which carbon atom in acetic acid would you predict would be the farthest downfield in your C-13 Spectrum?
Which of the following compounds would you expect to have the lowest Rf value on a silica gel TLC plate developed with dichloromethane? O A. Naphthalene O B. Phenyl acetate OC Butyric acid QUESTION 3 Which of the following compounds would you expect to have the highest Rf value on a silica gel TLC plate developed with dichloromethane? O A 2-octanone O B. Acetic acid C. 1-butanol OD. decane E. acetaldehyde