Lab Final Flashcards
TLC can be used to
purify small amounts of impure compounds and quickly indicate the quantity and identity of pure compounds in a mixture
TLC was used in lab to test
4 solutions of dissolved analgesic tablets to identify the compounds as Bayer, Walgreens, or Goody’s
Aspirin and Caffeine
Bayer
Acetaminophen
Walgreens
Aspirin, Caffeine, and Acetaminophen
Goody’s
The plate was developed in 100% hexanes (very non-polar). Which of the two spots is the more non-polar?
The one that traveled the furthest because it is more drawn to the hexanes
Organic compounds often used in products like Vicks vapor rub
Camphor
Secondary alcohol oxidized to form Camphor (a ketone)
Borneol
The Jones reagent contains chromium (VI), which is reduced to chromium (III) as the alcohol is oxidized. What visual indicator shows that the Jones reagent is reacting?
It starts a red-yellow color and turns green when it reacts.
State one safety hazard associated with the Jones Reagent.
It is toxic. If ingested can be very harmful.
Removes acids
5% sodium bicarbonate
Reduce remaining Cr6+ to less toxic Cr3+
5% Sodium Bisulfite
Removes excess water
Saturated sodium chloride
Reagent that will reduce carbonyl compounds, but is not as reactive as lithium aluminum hydride (LAH
NaBH4: Sodium Borohydride
What is the purpose of adding water and/or HCL at the end of the Sodium Borohydride reaction
To protonate the reaction as a means of neutralizing it.
Why can’t acetone be used as a solvent for reduction reactions that involve NaBH4 or LAH?
Because it turns the product into 2-propanol
When a carbonyl is reduced to an alcohol, where should the broad IR peak be?
around 3300 cm-1
When creating a solution for an NMR sample, why must the solvent be deuterated (using D2O instead of H2O)
Because the hydrogens from the H2O would interfere with the NMR results by showing 2 extra hydrogens that were not originally in the product.