Question

Why are hydrogen bonds associated with water $({H_2}O)$, but not with methane $(C{H_4})$?

Answer 1

Hydrogen bonding is developed between a hydrogen atom and a highly electronegative atom. We know that oxygen is a more electronegative atom than carbon. The hydrogen bonding mainly arises due to the dipole moment between the two molecules.

Complete answer:
A hydrogen bond is the attractive intermolecular force that arises due to the dipole-dipole interaction between a hydrogen atom that is bonded to a highly electronegative atom (an atom that has a greater pull for electrons). When one atom is more electronegative, it tends to spend more time near it than the other covalently bonded atom. This way, the more electronegative atom acquires a partial negative charge, while the other acquires a partial positive charge. Then, when many of these molecules are placed together, negative ends of the molecules are attracted to others’ positive ends, and vice versa.
When we talk about water, hydrogen is covalently bonded to the more electronegative atom oxygen. The O-H bond in the water is polar. And there is an uneven distribution of charge in the molecule and so there is an extra force of attraction between the water molecules. This force of attraction is hydrogen bonding.
In the case of methane, the C-H bonds are nonpolar; the difference in electronegativity between carbon and hydrogen is not large enough to create a dipole moment. Thus, no partial charge is created. And hence there is no hydrogen bonding.

Note:
The compounds having hydrogen bonding show abnormally high melting point and boiling point. The high melting and boiling point of the compound containing hydrogen bonds is because some extra energy is needed to break these bonds.