Question

How can you name chemical compounds from their formulae in the following cases?

Give examples in support of your answer

If a compound contains two nonmetals only

Answer 1

What elements make covalent bonds?

Covalent bonds form when two or more nonmetals combine. For example, both hydrogen and oxygen are nonmetals, and when they combine to make water, they do so by forming covalent bonds. Compounds that are composed of only non-metals or semi-metals with non-metals will display covalent bonding and will be classified as molecular compounds.

Steps of writing the formula

• The formula is written with the more electropositive element (the one further to the left on the periodic table) placed first, then the more electronegative element (the one further to the right on the periodic table).
• If there is only one of the first elements in the formula, the mono- prefix is dropped.(table given below)
• The first element in the formula is given the neutral element name, and the second one is named by replacing the ending of the neutral element name with -ide. A prefix is used in front of each element name to indicate how many atoms of that element are present:

1	mono-
2	di-
3	tri-
4	tetra-
5	penta-
6	hexa-
7	hepta-
8	octa-
9	nona-
10	deca-

For example,

${\mathrm{SO}}_3$	sulfur trioxide
${\mathrm{N}}_2\mathrm{O}$	dinitrogen monoxide
${\mathrm{N}}_2{\mathrm{O}}_5$	dinitrogen pentoxide