Why is hydrogen bonding more extensive in water than in hydrogen fluoride?
Answers
Hydrogen bonding occurs when there is an INTRAMOLECULAR bond between H and N, O or F. Hydrogen bonding is the INTERMOLECULAR bond, with high covalent character, between the hydrogen of one molecule and the O, N or F of an adjacent molecule.
There are twice as many hydrogen atoms per oxygen atom, as compared to HF, and therefore, twice as many potential hydrogen bonds.
The evidence is in the melting point (and boiling point) of the two. Since both are polar, and both have about the same number of electrons, then dipole interactions and London dispersion forces are about the same. The only major difference is the hydrogen bonding and since HF melts at -84C and boils at 19.5C, while water melts at 0C and boils at 100C, it is easy to see the evidence for the more extensive hydrogen bonding in water.
There are twice as many hydrogen atoms per oxygen atom, as compared to HF, and therefore, twice as many potential hydrogen bonds.
The evidence is in the melting point (and boiling point) of the two. Since both are polar, and both have about the same number of electrons, then dipole interactions and London dispersion forces are about the same. The only major difference is the hydrogen bonding and since HF melts at -84C and boils at 19.5C, while water melts at 0C and boils at 100C, it is easy to see the evidence for the more extensive hydrogen bonding in water.