BONDING
~Elements that are joined by chemical
bonds do not readily fall apart.
(Like picking up a puzzle)
~Atoms bond with other atoms by
using their valence electrons.
~Remember opposites attract.
(Positive and negative)
~The goal of an atom is too become
stable. Need a maximum number of
valence electrons (2 or 8).
4 ways to bond:
1. Losing electrons (Ionic Bond) (+)
2. Gaining electrons (Ionic Bond) (-)
3. Pooling electrons(Metals only)
4. Sharing electrons (Covalent Bond)
IONIC BONDS
Ionic Bond: Attraction that holds
oppositely charged ions close together.
Ion: Atom that is positively or
negatively charged because it has
gained or lost one electron.
*An atom that gains one or more
electrons becomes a negative ion or
anion.
*An atom that loses one or more
electrons becomes a positive ion or
cation.
Metals and nonmetals combine in an
ionic bond.
METALLIC BONDING –
POOLING
Metallic Bond: Form when metal
atoms share their pooled electrons.
In a metal, electrons are not held
tightly to an individual atom. The
electrons move freely among all the
ions in a metal.
The valence electrons in metal atoms
readily move from one atom to
another. This is called pooling.
Pooling electrons gives a metal its
characteristics. (Conductors,
malleable, tensile, and ductile)
COVALENT BONDING
COVALENT BOND: Chemical bond
formed when atoms share electrons.
Covalent Bond forms between
nonmetal elements.
Shared electrons are attracted to the
nuclei of both atoms.
Electrons move back and forth
between atoms, completing the outer
energy level.
Covalently bonded compounds are
called molecular compounds.
The atoms in a covalent bond are
neutral because the number of protons
and electrons is equal.
The neutral particle formed when
atoms share electrons is called a
molecule.
Double Bond: two pairs of shared
electrons
Triple Bond: three pairs of shared
electrons
Polar Bond: Unequal sharing of
electrons makes one side of the atom
more negative than the other side.
Nonpolar Bond: Equal sharing of
electrons.