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The atoms of all elements are made up of a
central nucleus with orbiting electrons.
◦ A nucleus is made up of positively charged
PROTONS and neutral NEUTRONS.
◦ ELECTRONS are negatively charged and orbit
around the nucleus.
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In order to organize elements we need to
classify them.
To classify and name an element we look at
the number of PROTONS that the atom has.
The number of PROTONS defines the element

To organize the elements we use the
PERIODIC TABLE. The periodic table organized
elements in the order of the number of
protons each atom contains
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How the table is actually organized

In each box of the periodic table there is
information about the element
B
Boron
5
Atomic Number
(The number of Protons)
Element symbol
Name of Element