Chapter 28 Appendix D: Dissociation Constants and pKb Values for Bases at 25°C

Name Formula K b pKb
Ammonia NH3 1.8 × 10−5 4.75
Aniline C6H5NH2 7.4 × 10−10 9.13
n-Butylamine C4H9NH2 4.0 × 10−4 3.40
sec-Butylamine (CH3)2CHCH2NH2 3.6 × 10−4 3.44
tert-Butylamine (CH3)3CNH2 4.8 × 10−4 3.32
Dimethylamine (CH3)2NH 5.4 × 10−4 3.27
Ethylamine C2H5NH2 4.5 × 10−4 3.35
Hydrazine N2H4 1.3 × 10−6 5.9
Hydroxylamine NH2OH 8.7 × 10−9 8.06
Methylamine CH3NH2 4.6 × 10−4 3.34
Propylamine C3H7NH2 3.5 × 10−4 3.46
Pyridine C5H5N 1.7 × 10−9 8.77
Trimethylamine (CH3)3N 6.3 × 10−5 4.20