Chimie Generale - Atomes et Molecules

Protons, neutrons, and electrons.

A subshell is determined by the azimuthal quantum number *l*.

The principal quantum number (*n*).

No two electrons in an atom can have the same set of four quantum numbers. The principe of exclusion.

Every orbital in a subshell is singly occupied with one electron before it is doubly occupied. This is a principle of maximum multiplicity. The needed energy to pair 2 electrons in the same box is superior to dispose electrons celibates in differents boxes.

The building order of the subshells follows the Klechkowski rule.The energy of subshells with the same n varies.

Electronegativity is the ability of an atom to attract electrons in a chemical bond.

Sigma bonds are formed by axial overlapping of orbitals, whilst pi bonds are formed by lateral overlapping of p orbitals after sigma bond formation.

The VSEPR theory (Valence Shell Electron Pair Repulsion) states that electron pairs in the valence shell of an atom repel each other and will therefore adopt an arrangement that minimizes this repulsion.

Atomic orbitals combine to form molecular orbitals. Some stabilize the bond (bonding orbitals), others destabilize it (anti-bonding orbitals).