Lab 2

Question 1

When using a UV lamp to visualize TLC spots you

Answer 1

should observe dark spots on a fluorescent background

Question 2

The leading edge of the solvent as it advances up your TLC by capillarity is called the

Answer 2

solvent front

Question 3

The numbers on the side of the TLC are the distance from the bottom of the plate, in centimeters. To calculate the Rf of the spot in lane P you should be dividing

Answer 3

(`Distance from starting point to solvent front) - (Distance from spot to starting point)

Question 4

The unit of Rf is:

Answer 4

Nonexistent

Question 5

Arrange the eluent solvents from least polar (1) to most polar (4).

Answer 5

Hexanes, diethyl ether, ethyl acetate, methanol

Question 6

T/F: The spotting line should be submerged in the solvent.

Answer 6

False

Question 7

In TLC, the eluent is the _______–
phase.

Answer 7

Mobile

Question 8

T/F: It’s not necessary to cover/cap your TLC jar or beaker

Answer 8

False

Question 9

Your TLC should be developed in a sealed jar containing a liquid eluent. This can take place….

Answer 9

in your fume hood, behind the yellow and black strip

Question 10

Using regular silica gel TLCs…

Answer 10

Less polar compounds move higher