Consider the following compounds ethanamine (i); diethylamine (ii); aniline (iii) and N - methylbenzenamine (iv) The correct decreasing order of pKb values of the compounds is:

Step-by-step solution

The basicity of amines is inversely proportional to their pK_b values. Higher basicity corresponds to a lower pK_b value. Comparing the basicity of the given compounds: 1. Diethylamine (ii) is a secondary aliphatic amine. It is the most basic due to the electron-donating inductive effect of two ethyl groups and favorable solvation. 2. Ethanamine (i) is a primary aliphatic amine. It is less basic than diethylamine due to fewer electron-donating groups. 3. N -methylbenzenamine (iv) is an aromatic amine where the lone