Writing Formulae For Covalent Compounds printable pdf download

Writing Formulae For Covalent Compounds

riting formulae for covalent compounds

Covalent compounds are (usually) made up of atoms of non-metal elements.

The formula for covalent compounds can be found by drawing electron sharing diagrams.

These can be based on the sharing of electron pairs by the merging of outer electron shells.

The following is a quick way to write the formula for a covalent compound. It is based on the

number of bonds that an atom forms. This is equal to the number of extra electrons that an

atom requires to reach the same electron arrangement as a noble gas.

Group 4

Group 5

Group 6

Group 7

Number of outer electrons

Number of ‘extra’ electrons

Number of bonds formed

An atom of hydrogen is 1 electron short of an atom of helium so hydrogen form s 1

bond.

Example: carbon fluoride

Step 1 :

Use the Periodic Table to write symbols for the elements.

Step 2 :

Use the Periodic Table to put in the number of bonds which will be formed by

each atom.

Step 3 :

Complete the bonding picture.

Step 4 :

Write the formula

Chemical Changes and Structure

Covalent bonding 11

Writing Formulae For Covalent Compounds