Covalent Bonding STRUCTURE AND BONDING Flashcards
What is covalent bonding?
Getting the stable electronic structure of a noble gas by sharing electrons.
The atoms in the molecules are held together by the shared pairs of electrons. These strong bonds are called covalent bonds.
Give an example of a giant covalent structure?
Diamond - each carbons atom forms 4 covalent bonds.
What are the properties of diamond?
Hard.
Very high melting and boiling points.
Cannot conduct electricity - there are no free electrons or ions to carry a charge no delocalised electrons because all the bonds are full.
Graphite is another covalent structure, what are is properties?
Soft and slippery - the layers easily slide over each other due to weak forces of attraction that are easily broken.
Can conduct electricity - the structure is only joined with 3 carbon atoms, leaving a delocalised electron.
What are the forces called that hold the atoms together in covalent bonds?
Intermolecular forced.
What happens to the intermolecular forces as the size of the molecule increases?
They increase with the size of the molecules. Therefore, larger molecules have higher melting and boiling points.
Talk about bonding in graphite.
There are no covalent bonds between the layers, only weak intermolecular forces. This means that the layers can slide over was just other easily.
Why can graphite conduct electricity?
Due to the delocalised electron. Graphite only have 3 carbon covalent bonds. This means the delocalised electron can moves freely throughout the structure allowing it to conduct electricity.