1. Isotopes

2. What is an isotope?
Every atom in an element has the SAME number of protons and electrons.
NOT ALL atoms in an element have the same neutrons.
AN ISOTOPE is an element that has a different number of neutrons and mass number

3. Example Oxygen has 8 protons. 8 neutrons Some oxygen atoms have
Mass # = 16
Some oxygen atoms have
8 protons, 9 neutrons
8 + 9 = 17 (mass #)
Some have 8 protons and 10 neutrons
Isotopes of O: Oxygen-16, oxygen-17, oxygen-18

4. Example 2 Carbon has 6 protons, 6 neutrons
Mass number = 12
Some carbon atoms have 6 protons, 8 neutrons
Mass number = 14
Isotopes of C: Carbon – 12, Carbon – 14

5. How do we write isotopes?
Oxygen – 16, Oxygen – 17, Oxygen – 18
Carbon – 12, Carbon – 14
O-16, O-17, O-18
C-12, C-14