C2 - Covalent Substances Flashcards
What are the forces like within a simple molecular substances?
Weak intermolecular forces.
What are is the melting/boiling point of simple molecular substances like and why?
Low because the intermolecular forces are easily broken.
What state are simple molecular substances in at room temperature?
Gas or liquid.
Why don’t simple molecular substances conduct electricity?
They have no ions so have no charge.
What is a giant covalent structure?
A macromolecule with strong covalent bonds.
Do giant covalent structures conduct electricity?
No, not even when molten.
Name 3 examples of giant covalent structures.
1) diamond.
2) silica.
3) graphite.
How many covalent bonds does diamond form and how does this affect its structure?
4 covalent bonds.
It is rigid.
Name a use of diamond.
Drill tips.
What is silica?
Sand.
What is each grain of silica?
One giant structure of silicon & oxygen.
How many bonds does graphite form? How does this affect its structure?
3 covalent bonds.
It has sliding layers with weak intermolecular forces, making it soft.
Name a use of graphite.
Pencils.
Why does graphite conduct electricity?
It has delocalised electrons.
What are simple molecular substances?
Small molecules with strong covalent bonds.
