What is a Water Molecule?
Oxygen and hydrogen are both non-metals.
An oxygen atom has 6
electrons in its
outer
shell.
Oxygen is in group 6 of the periodic table.
A hydrogen atom has 1 electron in its
outer shell.
Hydrogen can only form 1 bond.
Two hydrogen
atoms each share their
1 electron with oxygen
to form two covalent bonds and make
a water molecule (H2O).
This is a picture of a water molecule.
By sharing the two electrons where the shells touch
each hydrogen atom can count 2 electrons in its outer shell
and the oxygen atom can count 8 electrons in its outer
shell.
These full outer
shells with their shared electrons are now stable,
and the
H2O molecule will not
react further with other oxygen
or hydrogen
atoms.
Note the 2
pairs (4 electrons)
shared between the atoms.
Each electron pair is one bond. This
is called a single
covalent bond.
Water has two single covalent bonds.
The structural formula of a water molecule is written
Note the shape of the
water molecule,
with both hydrogens on the
same side of the oxygen atom.
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