6. Covalent Compounds

Question 1

What is a covalent bond?

Answer 1

A covalent bond is a shared pair of electrons between atoms.

Question 2

Where do Covalent bonds occur?

Answer 2

In non-metallic Metals and compounds of non-Metals.

Question 3

How can Covalent bonds in molecules be shown?

Answer 3

Dots and cross diagrams.

Question 4

Everything you need to know about Small Molecules:

Answer 4

~They contain a relatively small number of non-metal atoms joined together by Covalent bonds.
Going down Group 7, the molecules get larger and their melting and boiling points increase.

Question 5

Everything you need to know about Giant Covalent Structures:

Answer 5

~All the atoms in giant covalent structures are linked by strong Covalent bonds.
~These bonds must be broken for the substance to melt or boil.

Question 6

Diamond:

Answer 6

~It has a giant, rigid Covalent structure.

~There are no charged particles, so it does not conduct electricity.

Question 7

Graphite:

Answer 7

~It has a giant covalent structure and a very high melting point.
~It has a hexagonal structure.
~Layers can slide past each other, making graphite soft and slippery.
~One electron fro: each carbon atom in graphite is delocalised.

Question 8

Silicon dioxide (silica):

Answer 8

~Has a similar structure to diamond.
~Each oxygen atom is joined to two silicon atoms.
~Each silicon atoms is joined to four oxygen atoms.