Final answer:
Carbocaine is not an amide whereas procaine, lidocaine, and mepivacaine are amides because they contain the amide functional group. Procaine, specifically, reacts to form a slightly basic solution when used as novocaine.
Step-by-step explanation:
The correct option : d
An amide is a functional group characterized by a carbonyl group (C=O) linked to a nitrogen atom (N-H). Procaine, lidocaine, and mepivacaine all contain this characteristic amide linkage which is part of their molecular structure. Procaine, also known as Novocain, is a local anesthetic and is often used in its salt form, procaine hydrochloride. The procaine hydrochloride forms when procaine reacts with hydrochloric acid.
aProcaine has an ionization constant (Ka) of 7 x 10-6, indicating that it can act as a weak base in an aqueous solution. A 2.0% by mass solution of novocaine has a slightly basic pH because the procaine can accept hydrogen ions from water, creating a slight excess of hydroxide ions. Calculating the exact pH, [H3O+], and [OH-] of the solution would require additional steps including using the ionization constant (Ka) and the mass/volume percentage of the solution.