Final answer:
The salt formed by the reaction of dimethyl amine with HBr is called dimethylammonium bromide, where dimethyl amine acts as a base.
Step-by-step explanation:
The name given to the salt formed by the neutralization reaction of dimethyl amine in HBr is dimethylammonium bromide, and dimethyl amine acts as a base. Amines, including dimethyl amine, are bases that react with acids to form salts. In this case, the dimethyl amine would accept a proton (H+) from the hydrobromic acid (HBr) to form the salt dimethylammonium bromide. The reaction follows the concept of Brønsted-Lowry acid-base theory, where the base (dimethyl amine) accepts a proton from the acid (HBr).