Ppt
Bio1151
Chapter 2
The Chemical Context of Life
Matter consists of chemical
in pure
form
and in combinations called
compounds.
Each element contains a single kind of
atom
made of
,
, and
.
Electrons occupy different
with different
energy
. The outermost, or
, shell contains
electrons.
A
bond
is the
of a pair of
electrons between different atoms of a
. These bonds are strong and stable.
In a
covalent bond the atoms have different
electronegativities
and share the electrons
.
In an
bond,
charged atoms called
are formed.
Electronegativity can also result in other weak chemical interactions.
A
bond
forms from the attraction of charged regions of
molecules.
interactions
form when transiently charged regions of molecules attract each other.