an atom
the smallest particle of an element that still has its chemical property
a molecule
is made from two or more atoms joined together
- joined by attractive forced or chemical bonds
an element
only contains one type of atom
atomic number
number of electrons
also
number of protons
atomic mass
most of mass is in nucleus - so it is number of …..+….
number of protons + neutrons
how do you find number of neutrons?
atomic mass - atomic number
isotopes
atoms with the SAME number of PROTONS AND ELECTRONS
but DIFFERENT numbers of NEUTRONS
have the same atomic number but different mass number
Ions
charged particles, they are formed when an atom, or group of atoms, lose or gain and electron