Atoms and molecules

Atoms and molecules
In atoms, electrons orbit around nucleus in orbitals more or less far
from the core. The atomic weight depends on the number of protons in the nucleus, while properties
chemical depend essentially outermost electrons. Moreover, the nuclei
atomic are positively charged, while the electrons are negatively charged.
The four elements are best represented in living organisms are nitrogen, oxygen,
carbon and hydrogen (96.3% of body mass of Rights).
Following the electronic movements, when two atoms are close enough, and in
certain conditions, an electron can pass from one atom to another atom. The loss of electron
one corresponds to oxidation while the gain for each other is reduced.
Moreover, the sharing of electrons belonging to different atoms allows the formation
of molecules. Depending on their nature, these bonds are stronger or weaker. Thus, the connections
corresponding to the covalent sharing of electron pairs between atoms are strong bonds,
as opposed to hydrogen bonds or Van der Waals bonds, qualified links
low. The stability of the molecules depends on the number of bonds brought into play