P1C7 - Substance types Flashcards
What are small covalent molecules held together by?
Intermolecular forces called covalent bonds.
What is an intermolecular force?
Forces held within molecules
Why are small covalent molecules liquids or gases at room temperature?
Weak intermolecular forces that break.
What is diamond?
An allotrope of carbon
What are the properties of diamond?
- Giant covalent structure
- Each carbon atom is bonded to 4 other carbon atoms
- Strong covalent bonds
- Hard
- Doesn’t conduct electricity
- High melting point
What is graphite?
An allotrope of carbon
What properties does graphite have?
- Giant covalent structure
- Each carbon atom is bonded to 3 other carbon atoms
- Strong covalent bonds
- Soft
- Conducts electricity
Why is graphite soft?
- Weak intermolecular forces holding layers together
- Layers can easily slide over eachother
What are fullerenes?
Molecules of carbon atoms that take up hollow structures
What is the formula for buckminsterfullerene?
C60
What is graphene?
An allotrope of carbon
What is an allotrope?
A form of something.
What are the properties of graphene?
- COnducts electricity
- Light but strong
Why is graphene light BUT strong?
- Thickness of 1 atom
But - Strong covalent bonds
What are polymers?
Large, chain-like molecules that can extend for thousands of atoms.
