Zusammenfassung der Ressource
COVALENT BONDING
- bond length: single < double < triple
- bond strength: single < double < triple
- use VSEPR to predict the shapes of molecules
- pairs of valence electrons repel each other and will
take up positions to minimise these repulsions
- lone pairs repel more than bonding pairs
- giant covalent compounds
- have high melting points because
covalent bonds are broken when melting
- Examples
- silicon
- SiO2
- diamond
- graphite
- covalent molecular compounds
- non-polar molecules
- polar molecules
- difference in electronegativity: electrons lie
more towards one atom than another
- shape of molecules: if the dipole moments of
individual bonds cancel, the molecule is not polar
- only intermolecular forces are broken when melting
- Van der Waals forces
caused by instantaneous
and induced dipoles
- dipole-dipole forces
- hydrogen bonds