Covalent Bonding Flashcards
What is a covalent bond?
A bond that is formed when two non-metals share a pair of electrons
Why do simple molecular compunds have low melting and boiling points?
They have weak intermolecular forces which only require a little energy to overcome
Do simple molecular compunds conduct electricity?
No because there are no charged particles
Do giant covalent structures have a high melting point?
Yes because they have lots of strong covalent bonds which require a lot of energy to break
Name two giant covalent structures
- Graphite
- Diamond
Describe the structure of graphite
Each carbon atom bonded to 3 other carbon atoms.
Layers of hexagonal rings of carbon atoms
Weak intermolecular forces between layers
One delocalised electron per carbon atom
Describe and explain the properties of graphite
- Graphite is soft / slippery because there are only weak intermolecular forces between layers which allow the layers to slide over one another.
- Graphite conducts electricity because there is one delocalised electron per carbon atom. The delocalised electrons are mobile charges.
Describe the structure of diamond
- All carbon atoms are covalently bonded to four other carbon atoms
- No delocalised electrons
Describe the properties of diamond
- Very hard
- Very high melting point
- Doesn’t conduct electricity as there are no charged
What are the general properties of non-metals?
- Low boiling points
- Poor conductors of electricity
- Brittle when solid
