What is h bond

The water molecule

The water molecule has an angled structure. The angle between the two hydrogen atoms is approx. 104 degrees (°). This angled structure results from the two non-bonding electron pairs that the oxygen atom possesses (these are indicated by the two lines above the oxygen atom).

Water molecules are dipoles
In the water molecule, two hydrogen atoms are bound to an oxygen atom via an electron pair bond. The electron pair bond consists of two electrons and is indicated by a line.

A measure of the force to attract the electrons of the electron pair bond is called electronegativity (EN = measure of how strongly an atom attracts common bonding electrons). Different atoms have a different electronegativity value. The element with the highest electronegativity is fluorine (EN = 4). Oxygen has an electronegativity of 3.5 and hydrogen of 2.1. This in turn has an impact when atoms come together to form a molecule, as is the case with water. In the water molecule, oxygen has a greater electronegativity than hydrogen and thus attracts the electrons of the two electron pair bonds to its side. This results in a negative partial charge for the oxygen atom (denoted by the ancient Greek letter “delta”; δ-). The hydrogen atoms, on the other hand, receive a positive partial charge (δ +).

The angled structure and the different electronegativity values ​​of oxygen and hydrogen result in a negative center of charge on the oxygen side and a positive center of charge on the other side of the water molecule for hydrogen.

Water molecules are thus a dipole or dipole molecule (double pole).