Basic strength of different alkyl amines depends upon:A. + I effectB. steric effectC. solvation effectD. all of these

The basic strength of different alkyl amines depends on several factors, including:

A. +I effect (Inductive Effect): Alkyl groups are electron-donating via the inductive effect. This means that they push electron density towards the nitrogen atom, increasing its availability for protonation, and hence increasing the basicity.

B. Steric effect: The size and number of alkyl groups attached to the nitrogen can affect the basicity of amines. Larger alkyl groups can create steric hindrance, making it more difficult for the amine to accept a proton, thereby decreasing its basicity.

C. Solvation effect: The ability of the amine to form hydrogen bonds with the solvent (usually water in aqueous solutions) plays a significant role. In aqueous solutions, the solvation of the protonated amine (the ammonium ion) stabilizes it. Primary amines are generally better solvated than secondary or tertiary amines, because they have more hydrogen atoms available to form hydrogen bonds with water.

Therefore, the basic strength of alkyl amines is influenced by the combined effects of the inductive effect, steric hindrance, and solvation, making the correct answer:

D. All of these