Question
In: Chemistry
Which of the following statements is true for TLC when silica gel is used as the...
Which of the following statements is true for TLC when silica gel is used as the stationary phase? Note: More than one statement can be correct.
a) The more polar a compound, the more it will be attracted to the mobile phase.
b) Compounds with low polarity have higher Rf-values when solvents with lower polarity are used.
c) The higher the solvent polarity, the lower is the Rf-value of a compound.
d) The more polar a compound, the more it will be attracted to the stationary phase.
Solutions
Expert Solution
False: a) The more polar a compound, the more it will be attracted to the mobile phase. Because Silica Gel is a polar stationary phase. More polar compound will easily bind to the silica gel and cannot be easilt attracted by mobile phase.
True: b) Compounds with low polarity have higher Rf-values when solvents with lower polarity are used. Because low polarity compound will not bind the polar silica gel easily and can travel up in the TLC and will have higher Rf value (Rf value: = distance traveled by compound ÷ distance traveled by solvent front.)
False: c) The higher the solvent polarity, the lower is the Rf-value of a compound. As polarity of the solvent increase distance travel by the compound will increase and thereofre Rf-value will increase
True: d) The more polar a compound, the more it will be attracted to the stationary phase. Polar compound can easily attaracted by polar stationary phase i.e. silica gel
queen_honey_blossom answered 2 years agoRelated Solutions
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