Page 71 - The Miracle in the Atom

The Second Step On The Path To Matter: Molecules

tually, the universe. If atoms did not have such a tendency based on this
principle, some vital molecules would not exist. Yet, from the first moment
they were created, atoms have been serving in the formation of molecules
and matter in a perfect manner thanks to this tendency.

Covalent Bonds Fluorine atom Fluorine molecule (F )
2
Scientists who studied the bonds
between atoms faced an interesting situ-
Water molecule (H O)
ation. While some atoms swap electrons 2
for bonding, some of them share the elect-
rons in their outermost shells. Further re- Hydrogen Oxygen
atom atom
search revealed that many molecules that
Some atoms form new molecules by
are of critical importance for life owe the-
covalent bonding, sharing the electrons
ir existence to these 'covalent' bonds. in their outer orbits. 25
Let us give a simple example to
explain covalent bonds better. As we mentioned previously on the subject of
electron shells, atoms can carry a maximum of two electrons in their inner-
most electron shells. The hydrogen atom has a single electron and it has the
tendency to increase the number of its electrons to two to become a stable
atom. Therefore, the hydrogen atom forms a covalent bond with a second
hydrogen atom. That is, the two hydrogen atoms share each other's single
electron as a second electron. Thus, the H molecule is formed.
2

Metallic Bonds
If a large number of atoms come together by sharing each others' elect-

Metallic Bonding
The bonds between
metal atoms are
very different from
other forms of
chemical bonding –
each metal atom
contributes its outer
electrons to a com-
mon pool. This "sea
of electrons"
explains a key prop-
erty of metals – their
Electron ability to conduct
electricity. 26
Aluminium ion

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