How strong is a hydrogen bond?
Hydrogen bond
from weak (1–2 kJ mol−1) to strong (161.5 kJ mol−1 in the ion HF−
2
Hydrogen bonds can vary in strength from weak (1–2 kJ mol−1) to strong (161.5 kJ mol−1 in the ion HF−
2).[11][12]  Typical enthalpies in vapor include: