Methods Of Purification Of Organic Compounds

Step 1: Understanding the factors affecting basic strength of amines. The basicity of an amine depends on its ability to donate a lone pair of electrons on the nitrogen atom. Several factors influence this ability: Inductive Effect: Electron-donating groups (+I effect) increase electron density on nitrogen, enhancing basicity. Conversely, electron-withdrawing groups (-I effect) decrease basicity. Steric Hindrance: Bulky groups around nitrogen hinder solvation and protonation, reducing basicity. Solvation Effect: The interaction of the amine with solvent molecules affects its ability to stabilize the conjugate acid form, influencing basic strength.
Step 2: Eliminating incorrect Option.
- Solubility in organic solvents (Option iv) does not directly influence the intrinsic basic strength of amines.
- Correct factors: Inductive effect (i), Steric hindrance (ii), and Solvation effect (iii) play significant roles in determining basicity.
Thus, the correct answer is (B) (i), (ii), and (iii).

Step 1: The reducing power of a species is related to the magnitude of its reduction potential. A more negative reduction potential indicates a stronger tendency to lose electrons (thus, a stronger reducing agent).
Step 2: The species with the lowest reduction potential will be the best reducing agent:
- , with , indicates that can be reduced to , so is a relatively weak reducing agent.
- , with , indicates that Al is the strongest reducing agent due to the very negative reduction potential.
- , with , shows that has the weakest reducing power among the three. Thus, the correct order of reducing power is: