Chapter 1. Carbon Compounds and Chemical Bonds. Organic Chemistry. The chemistry of the compounds of carbon History- -Unofficially, Organic is one of the oldest sciences -Officially, it is one of the youngest. History.
Carbon Compounds and Chemical Bonds
-Unofficially, Organic is one of the oldest sciences
-Officially, it is one of the youngest
F > O > Cl,N > Br > C,S > H,P
5) Equivalent resonance structures make equal contributions to the overall structure.
6) The more stable a structure, the more it will contribute to the overall structure:
a) The more covalent bonds a structure has, the more stable it is.
b) Structures in which all atoms have octets are more stable
c) Opposite charge separation decreases stability
d) Structures with negative charges on highly electronegative atoms are more stable than those with negative charges on less electronegative atoms
WHAT YOU NEED TO KNOW:
1s < 2s < 2px = 2py = 2pz < 3s
1) Aufbau Principle: Orbitals are filled so that those of lowest energy are filled first.
2) Pauli Exclusion Principle: Only two electrons are allowed in each orbital and must have opposite spins
3) Hund’s Rule: When multiple orbitals of equal energy are present, each orbital receives one electron before any pairs are created.
sp < sp2 < sp3
% s 50% 33% 25%
1) We consider molecules (or ions) in which the central atom is covalently bonded to two or more groups.
2) We consider all of the valence electron pairs of the central atom
-Shared electrons are called bonding pairs
-Unshared electrons are called non-bonding or unshared pairs
3) Because electrons repel each other, they stay as far away from one another as possible
Nonbonding repulsion > bonding
4) We arrive at the geometry of an atom by considering both bonding and nonbonding electrons but the shape of the molecule by referring to the position of nuclei.
See table 1.3 on page 47.