| Electron pair repulsion theory states | negative charge - repulsion
The electrons surrounding the central atom determine the shape of the molecules. As they repel they are arranged as far apart as possible so the arrangement lowers repulsion |
| Tetrahedral | 4bonding regions
109.5 degrees |
| Pyramidal | 3 bonding regions
1 lone pair 107 degrees |
| Non linear | 2 bonding regions
2 lone pairs
104.5 degrees |
| Linear | 2 bonding region
180 degrees |
| Triagonal planar | 3 bonding regions
120 degrees |
| Octahedral | 6 bonding regions
90 degrees |
| Electronegativity definition | The attraction of a bonded atom for the pair of electron in a covalent bond |
| Factors affecting electroegatvity | - The nuclear charges are different
- The atoms may be different sizes
-The shared pair of electrons may be closer to nucleus than the other |
| ELECTRONEGATIVITY DIFFERENCE 0= | COVALENT |
| EN DIFFERENCE +1.8 = | IONIC |
| AN ELECTRONEGATIVITY DIFF BETWEEN 0-1.8= | POLAR COVALENT |
| Non polar bonds terms | bonded atoms are the same or same or siimiliar electronegativity |
| delta + and delta - are given | larger e neg gets delta - smaller e neg gets delta + |
| Which molecules have an overall dipole | non-symmetrical molecules so polar molecules have a dipole overall
eg. pyramidal and non linear |
| Polar covalent bond definition | Shared paired of electrons where the electron is not shared equally so e neg difference |
| Dipole definition | Charged separation across a bond with one atom having a delta + charge and one item with delta - charge |
