Covalent Bonds Flashcards
Describing the forces within a covalent?
The electrostatic attraction between the nuclei of bonded atoms and a shared pair of electrons.
What is a molecule?
A group of atoms joined by covalent bonds.
Why do simple molecular substances have low melting & boiling points?
There are weak forces between molecules which are easy to break (intermolecular forces)
Why don’t simple molecular substances conduct electricity?
The molecules are free to move, but also neutral, so cannot conduct electricity
What is the bonding in a metal?
Metallic
What is the structure of a metal?
Giant metallic lattice
What is the bonding in a metal and non-metal?
Ionic
What is the structure of a metal and non-metal?
Giant ionic lattice
What is the bonding in a non-metal?
Covalent
What is the structure of a non-metal?
Simple molecular
What is the structure of C60 fullerene?
A simple molecular substances
What is the melting point of C60 fullerene and why?
Relatively low, not as low as other simple molecular substances becasue it has a high molecular mass
Does C60 fullerene conduct?
No because its molecules are neutral
What structure does silicon dioxide have?
Giant covalent structure
Why does silicon dioxide have a very high melting point?
It has a giant covalent structure, so there are lots of covalent bonds which a very strong and takes a huge amount of energy to overcome
Why does silicon dioxide does not conduct electricity?
None of its electrons are mobile because they are all stuck in bonds
What structure does diamond have?
Giant covalent structure
Why does graphite conduct electricity?
It’s structure contains delocalised electrons which are free to move
What is one use for diamond?
Drill bits, cutting
What is a use for graphite?
Solid lubricant
