Download Structure of The Atom

STRUCTURE OF THE ATOM
Not the Adam
BASIC STRUCTURE OF THE ATOM
A positively charge proton
 A neutrally charged neutron
 The negatively charged electron travels around
the nucleus

RELATIVE MASSES OF THE SUB-ATOMIC
PARTICLES
Proton has a mass of 1.0073 amu or 1 amu
 Neutron has a mass of 1.0087 amu or 1amu
 Electron has a mass of 5.49 x 10-4 amu

One amu equals 1.66 x 10-27kg
 Atomic Mass Unit (amu) is a unit of mass equal
to one-twelfth (1/12) of the mass of a carbon 12
atom.

THE RELATIVE MASSES OF THE PARTICLES
WHAT IS IN THE NUCLEUS?

The nucleus contains the
Protons – positively charged
 Neutrons – neutral charged


The nucleus has a positive charge
RELATIVE SIZE OF NUCLEUS
ATOMIC NUMBER
The atomic number represents the number of
protons in an element
 Each element has its own Atomic Number



The number of protons is what determines what type
of atom.
The number of protons equals the number of
electrons in an atom
ATOMIC SYMBOL
Elements are represented by a symbol
 The symbol is either one upper case letter or an
upper case and a lower case








O
C
Na
Mg
Si
Cl
NEVER MG or NA or SI or CI
ON PERIODIC TABLE

Top number

Atomic number
Symbol
 Atomic mass


The bottom number
ATOMIC MASS
 The
atomic mass gives the mass of the protons
and neutrons in an atom
 The
atomic mass less the atomic number gives
the number of neutrons
#
of Neutrons = Atomic mass-Atomic Number
DETERMINE THE NUMBER OF NEUTRONS
IN
Ca
H
 Bi
 Mo
O

20 neutrons
 0 neutrons
 126 neutrons
 54 neutrons
 8 neutrons

ATOMIC WEIGHT
Elements exist in different forms or isotopes in
nature
 Every atom of an element has the same number
of protons and electrons but different number of
neutrons
 The atomic weight of an element listed on the
periodic is the weighted average of all the
naturally occurring isotopes
