Matter & The Atom

Matter is made of atoms

Atomic Structure Nucleus Protons Neutrons Electrons

Atomic Structure Electrons Tiny, very light particles Have a negative electrical charge (-) Move around the outside of the nucleus

Atomic Structure Protons Much larger and heavier than electrons Protons have a positive charge (+) Located in the nucleus of the atom 

Atomic Structure Neutrons Large and heavy like protons Neutrons have no electrical charge Located in the nucleus of the atom 

Atomic Structure

Describing Atoms Atomic Number = number of protons The number of protons gives the atom its NAME

In a neutral atom, the # of protons EQUALS the number of electrons

Describing Atoms Atomic Mass Number (amu)- equal to the number of protons plus neutrons. Therefore, the number of neutrons equal the atomic number subtracted from the atomic mass number.