If you run a compound on 4 different TLC plates using the following four different solvent systems which solvent system would give the largest Rf value for the compound? pure ethyl acetate 25% heptane and 75% ethyl acetate 50% heptane and 50% ethyl acetate O pure heptane

In the table below, record the color that you observe for each spot or component of each spot after the run is completed. For the retention factor, R₁, write in the numerator (top) the number of mm that the spot has moved and in the denominator (bottom) the number of mm that the solvent has moved from the point where the samples were 'spotted. Calculate the Rf vale for each spot or component of each spot. Im having a difficult time finding the Retention Factor for M&Ms by using Salt water and seeing how much each color moves Instructions Coffee filters usually are round, but it's easier to compare your results if the paper is rectangular. So, your first task is to cut the coffee filter into a rectangle. Measure and cut a 2-3/4" by 7" strip from the middle of a coffee filter. This is easily done by folding the filter in half (to make a half-circle) and then folding the half-circle into thirds. Cut along the 13-fold lines and trim the ends to make a rectangle. 2. Using a pencil (ink from…

Plant pigments in spinach were separated with TLC with cellulose as thestationary phase and 80/20 diethyl ether/acetone mixture as themobile phase. If needed, the solvent structures in the lab Appendix.1. Determine the Rf values of each plant component on this TLC plate.2. Arrange the plant components from most polar to most nonpolar.  Please answer both 1 and 2 (picture below is the same question attached )

There were 2 spots on the TLC that did not match up with any of the standards. What were the Rf values of these spots? Identify what these chemical species might be and draw their structures. Solvent was 3:1:1 n-butanol/acetic acid/water. First plate is TLC plate 1. Second plate is TLC plate 2.

See image below

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One of the main differences between TLC and column chromatography is the direction in which the mobile phase moves. Group of answer choices True False

4 You were assigned to determine the concentration of an unknown starch solution. [This unknown is different from Dr. Ford's unknown.] So you prepared a cuvette by mixing 5 drops of your unknown starch solution + 5 drops of water +3 mL buffer + 1 drop of iodine. You used the same spectrophotometer Dr. Ford used to measure the absorbance of your unknown starch mixture and the absorbance was 0.127. What is the concentration (in micro-g starch/micro-L) of your unknown starch solution? Assume that 1 drop of the unknown out of starch solution = 40 micro-L. Give a numerical answer with 3 sig figs without any unit. Answer:

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You must separate three different compounds with reversed phase HPLC. Compound 1 is an acid (pKa = 4.3), compound 2 is neutral compounds and compound 3 is a base (pKa = 9.6). As eluent, use 30/70 (v / v)% methanol / pH 3.0 formic acid buffer. The retention time and the top width at the base of the top for the three components are presented below. You can assume the dead time to 1.2 minutes in your calculations.Compound Retention time [minutes] Peak width [seconds] 1 10.1     282 5.0 143 6.1 17a) Calculate the efficiency (number of theoretical bases) for component 1.b) Calculate the selectivity and resolution between components 1 and 2.c) When you increase the pH of your eluent to pH 6, how will the retention be affected (increase, decreaseor unchanged) for the different associations (1, 2 and 3) ?, justify your answer.d) How retention factors are generally affected by an increase in the proportion organicallymobile phase solvents for reversed phase HPLC separations ?, justify your…