Question

What would be the result of failing to mark the solvent front after developing a TLC plate? Would this affect

your ability to calculate component R

f

values? Why or why not?

2. What would happen if your origin line was oriented so low on the TLC plate that when it was lowered into the

TLC chamber it was positioned below the level of the developing solvent (eluent)?

3. Assuming that the separation of a binary mixture in ideal

circumstances (concentrated spotting) would be

relatively small (less than 0.5 cm), what would be the result of applying too large a spot of this mixture to the

TLC plate? How would it affect your ability to distinguish one component from the other on the

plate? How

would it affect your R

f

values? Draw a sample TLC plate to help illustrate your answer.

4. Unknown compound Q is spotted on a TLC plate that is then developed in cyclohexane. The solvent front is

measured at 5.2 cm and the distance traveled b

y compound Q is measured at 3.4 cm. A sample of

acetaminophen is spotted on a TLC plate that is then developed in cyclohexane. The solvent front is

measured at 4.15 cm and the distance traveled by

acetaminophen

is measured at 2.70 cm. What can be

determined abo

ut the identity of compound Q in light of this data?

5. Describe how TLC could be used to monitor a reaction’s progress (product & byproduct formation) in a

research/teaching laboratory.