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The result of a TLC experiment showed that Compound X has an Rf values of 0.75 on a silica plate using ethyl acetate (CH₃CO₂Et) as the mobile phase. Indicate if the Rf values of Compound X would be higher or lower in each of the following solvents. Briefly explain your reasoning for full credit, simply stating "higher" or "lower' will receive no credit. The structures of the solvents have been provided in the box to the right.

a. Dichloromethane
c. 50:50 Hexane:Ethyl Acetate
b. Toluene
d. 95:5 Ethyl Acetate:Methanol

User Quaneesha
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Final answer:

The Rf value of Compound X is 0.75 using ethyl acetate as the mobile phase. The Rf values of Compound X would likely be lower in dichloromethane and higher in toluene. The Rf value of Compound X could vary in a 50:50 hexane:ethyl acetate mixture and would likely be higher in a 95:5 ethyl acetate:methanol mixture.

Step-by-step explanation:

The Rf value of Compound X refers to the distance traveled by Compound X relative to the distance traveled by the solvent front in a TLC experiment. A higher Rf value indicates that the compound is more soluble in the solvent and thus travels further on the TLC plate. In this case, Compound X has an Rf value of 0.75 using ethyl acetate as the mobile phase.

a. Dichloromethane (CH2Cl2): The Rf value of Compound X would likely be lower in dichloromethane compared to ethyl acetate because dichloromethane is a less polar solvent and may have lower solubility for Compound X.

b. Toluene: The Rf value of Compound X would likely be higher in toluene compared to ethyl acetate because toluene is a more nonpolar solvent and may have higher solubility for Compound X.

c. 50:50 Hexane:Ethyl Acetate: The Rf value of Compound X could vary depending on the proportion of hexane and ethyl acetate in the mixture. If the proportion of ethyl acetate is higher, the Rf value may be similar to or higher than the Rf value in pure ethyl acetate. If the proportion of hexane is higher, the Rf value may be lower than the Rf value in pure ethyl acetate.

d. 95:5 Ethyl Acetate:Methanol: The Rf value of Compound X would likely be higher in 95:5 Ethyl Acetate:Methanol compared to pure ethyl acetate because methanol is slightly more polar than ethyl acetate and may enhance the solubility of Compound X.

User Cesar Loachamin
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