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Atomic Structure

What is Covalent Bonding?

When non-metals react with non-metals they share electrons
and form a covalent bond. Covalent means sharing.
If you do not know whether an element is
a metal or a non-metal, see the periodic table.

A covalent bond forms because of the electrostatic attraction
between the nuclei of the atoms (that are positive)
and the shared electrons (that are negative).
There are no ions present (no + or - charges) because the
electrons are shared, not transferred from one atom to another.

One pair of shared electrons form a single covalent bond.
Two pairs of shared electrons form a double covalent bond.
Three pairs of shared electrons form a triple covalent bond.

What is a Molecule?

Only covalent compounds are called molecules.
If the compound is ionic it is not called a molecule.

Covalent compounds containing a small number of atoms
are called simple molecules. Simple means
that only a small number of atoms are present.
If a huge number of atoms are
present it would be called a giant molecule.

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