Acid-Base Extraction Flashcards
What three compounds did we separate in the acid-base extraction?
Benzoic Acid, 1,4-dimethoxybenzene, and 2-napthol
What is the pKa of benzoic acid?
4.17
What is the pKa of 1,4-dimethoxybenzene?
44
What is the pKa of 2-napthol?
9.9
What is our initial solvent in the acid-base extraction?
t-butyl methyl ether
Why did we add saturated sodium bicarbonate to our mixture?
Sodium bicarbonate is a weak base, and will react with benzoic acid because it is our strongest acid. The sodium forms a salt with the ether.
What is the spectator ion in the reaction between sodium bicarbonate and benzoic acid?
Sodium
How do we turn the salt back into the benzoic acid?
We add hydrochloric acid (which is a stronger acid) and the acid-base mechanism functions to make benzoic acid again.
What do we use to stir our reaction tubes?
Glass Stirring Rod
What did we use to crystalize the benzoic acid?
Ice Bath
What did we use to collect the benzoic acid crystals?
Hirsh Funnel
What did we add to the 2-napthol and 1,3-dimethoyxbenzene mixture and why?
We added aqueous sodium hydroxide which is a strong base. It functions as the acid-base mechanism to remove the acidic proton off the 2-napthol.
Why did we add saturated sodium chloride to the 1,4 dimethoxybenzene?
The saturated sodium chloride helps us remove most of the water.
How do we remove all of the left over water from the 1,4-dimethoxybenzene after we’ve added the saturated sodium chloride?
Anhydrous Calcium Chloride Pellets
