They are weak acids because they dont fully dissociate. Meaning that only part of the solution of carboxylic acid will split in RCOO- and H+
There is no reaction. Acetic acid is a kind of carboxylic acid.
Because the conjugate bases are unstable the carboxylic acids are weak acids.
No, Acetic acid (ethanoic acid, CH3COOH) is the second simplest. Methanoic acid (formic acid) is the simplest with the formula HCOOH.
Carboxylic acids are weaker