amines

Question

The order of basicity of amines in aqueous solution is:

RankGuru · Accepted Answer

In aqueous solution, the basicity of amines is determined by three factors:
1. **Inductive Effect**: Alkyl groups are electron-donating ($+I$), increasing electron density on Nitrogen. Order: $3^\circ > 2^\circ > 1^\circ > NH_3$.
2. **Solvation Effect**: The stability of the conjugate acid ($R_nNH_{4-n}^+$) through H-bonding with water. Order: $1^\circ > 2^\circ > 3^\circ$ (more H-atoms mean better solvation).
3. **Steric Hindrance**: Bulky alkyl groups hinder the approach of a proton. Especially significant for $3^\circ$ amines.
- **Result**: The interplay of these effects results in the order: **Secondary ($2^\circ$) > Primary ($1^\circ$) > Tertiary ($3^\circ$) > $NH_3$** (for methyl substituted amines).

Rank Guru

amines

Select the correct option:

More amines Practice Questions

Gas phase basicity order (strongest base first) is typically:

Correct decreasing basicity order in aqueous solution: