There are hydrogen bonds in water.
The notion of a hydrogen bond is used in the field of chemistry . The concept refers to a type of bond that is produced from the attraction between a hydrogen atom and a negatively charged oxygen, fluorine or nitrogen atom . This attraction, for its part, is known as dipole-dipole interaction and links the positive pole of one molecule with the negative pole of another.
The hydrogen bond can link different molecules and even different sectors of the same molecule . The hydrogen atom, which has a positive charge, is known as the donor atom , while the oxygen, fluorine or nitrogen atom is the acceptor atom of the bond.
Where can hydrogen bonds be found?
Hydrogen bonds appear in DNA , water and proteins , for example. Due to its existence, phenomena of great importance occur, which even appear on a daily basis. The boiling point of water , the lower density of ice compared to liquid water and the consistency of glycerin are linked to the presence of hydrogen bonds in the molecules.
In addition to all the above, it is worth knowing in depth another series of important data about the so-called hydrogen bonds:
-The substance in which they are most effective is water.
-There are various works and investigations that, over the years, have been carried out on bridges of this type. However, one of the most significant is the one that establishes that the distance between the oxygen atoms that take part in them is 0.28 nm, that is, 0.28 nanometers.
-It can be said that they are a unique case in terms of the dipole-dipole class interaction.
DNA has hydrogen bonds.
-Among the entire set of intermolecular forces that exist, it is considered that the bridges we are addressing are, without a doubt, the most important. And its strength can reach up to 155 KJ per mole.
-The atoms that, as a general rule, are those that participate in the development and creation of hydrogen bonds are fluorine, nitrogen or chlorine.
-It is important to know that any hydrogen bond can be subdivided into what has been called a symmetrical hydrogen bond. This is a term that refers to a bond that is much stronger, that can occur in ice that is subjected to high pressures and that is characterized because the hydrogen atom is at an equidistant distance from the atom to which it It is covalently linked.
Features and properties
Many of the peculiarities of hydrogen bonds are due to the weak attractive force they have compared to covalent bonds. Due to this characteristic, substances undergo changes in their properties . The melting point of a substance, to cite one case, can be related to this particular attraction of the hydrogen bond.
It must be taken into account, therefore, that hydrogen bonds have different values regarding the energy of their bonds, which is usually expressed in kJ/mol .