What is hydrogen bonding?

[alexfwang3g]

A synopsis of the question above in addition to an explanation of why they have to be F, O, or N.

[Adrianh72]

The elements in the second period, F,O, and N have the electronegativity needed to form these bonds.

[Frederick Keith_4C]

Hydrogen bonding is a type of electrostatic attraction between a hydrogen atom that is covalently bonded to another atom that is more electronegative than itself, particularly those of the second period:
Fluorine
Oxygen
Nitrogen
Hydrogen bonds are typically weaker than ionic and covalent bonds, but are stronger than Van Der Waals interactions.

[405268063]

Hydrogen bonds form between oxygen, nitrogen, and fluorine atoms and hydrogen atoms. Oxygen, nitrogen, and fluorine are the only ones that are electronegative enough for this type of bond. But, I would also remember that hydrogen bonds are fairly weak.