Question

The minimum no of h-bond formed h2o molecule with other h2o molecule is

Answer 1

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

F−H···:F (161.5 kJ/mol or 38.6 kcal/mol), illustrated uniquely by HF2−, bifluorideO−H···:N (29 kJ/mol or 6.9 kcal/mol), illustrated water-ammoniaO−H···:O (21 kJ/mol or 5.0 kcal/mol), illustrated water-water, alcohol-alcoholN−H···:N (13 kJ/mol or 3.1 kcal/mol), illustrated by ammonia-ammoniaN−H···:O (8 kJ/mol or 1.9 kcal/mol), illustrated water-amideHO−H···:OH+
3 (18 kJ/mol[13] or 4.3 kcal/mol)

The X−H distance is typically ≈110 pm, whereas the H···Y distance is ≈160 to 200 pm. The typical length of a hydrogen bond in water is 197 pm. The ideal bond angle depends on the nature of the hydrogen bond donor. The following hydrogen bond angles between a hydrofluoric acid donor and various acceptors have been determined experimentally:[14]