2. Isotopes
 Atoms of the same element can have
different numbers of neutrons; the
different possible versions of the atom
of an element are called isotopes
 Written as a symbol and a number i.e.
C 14 is an isotope of carbon called
Carbon 14

4. Ions
▪An atom with a positive or
negative charge
▪Atoms are neutral unless they are
bonding

5. Ions
▪Atoms which gain electrons will
have a negative (-) charge and
become negative ions.
▪Atoms which lose electrons will
have a positive (+) charge and
become positive ions.