Sample Quiz for the Catalytic Hydrogenation Experiment

 

1) The catalytic hydrogenation experiment which you will do in lab has advantages over other techniques which convert an C=O group to a C-H2 group in that it uses less toxic and flammable reagents than these other methods. Which of the following is a name-reaction which is used to convert ketones and aldehydes to hydrocarbons?

  1. Wittig
  2. Boulveault-Blanc
  3. Clemmensen
  4. Eschweiler-Clarke

2) "Pd-C" is:

  1. phosphorus treated with deutero hydrogen
  2. palladium mixed with cadmium
  3. platinum on carbon
  4. palladium on charcoal (or carbon)

3) Why is it necessary to cool the flask before adding the Celite?

  1. otherwise, the finely powdered Celite will cause the solution to froth and perhaps bubble out of the container
  2. because the Celite reacts explosively with water at high temperatures
  3. to slow the reverse reaction of diphenylmethane to benzophenone
  4. to expedite the crystallization of diphenylmethane

4) The product, diphenylmethane, is isolated properly by a student and is very pure. Will the compound be a solid or a liquid?

  1. a solid
  2. a liquid
  3. it depends on how hot it is in the lab room

5) List 2 regions in the IR spectra that help you distinguish between product and reactant.

  1. 3500-3200 (O-H stretch) and 1750-1650 (C=O stretch)
  2. 3100-3000 (aromatic C-H stretch) and 1600-1585 (C-C stretch)
  3. 3500-3200 (O-H stretch) and 1600-1585 (C-C stretch)
  4. 3000-2800 (alkane C-H stretch) and 1750-1650 (C=O stretch)

6) Draw the product of the following reaction. When finished compare with the answer.

 7) You isolated diphenylmethane and obtained the spectrum below. Is the diphenylmethane pure? If not, what is it contaminated with? (As a reference, check the organic chem web site's "running an NMR" page for common contaminants--scroll to the bottom of the page.)

Answers.