1. Isotope Class Notes

2. Pair Share
Tell your neighbor what you know about isotopes

3. Isotope Video

4. Subatomic Particles
Label the atom:

5. What are Isotopes?
First, do you remember how to find the number of neutrons in an atom?
Write the equation down in your notes

6. What are Isotopes
Isotopes are atoms that have a different number of neutrons.
An atom is still the same element if it is missing a neutron- it’s just a different version!
Neutrons can be added to an atom without altering the number of protons and electrons it has.

7. Carbon Isotopes
For example, the element carbon has 13 different isotopes!
You are familiar with C-12 (the C stands for carbon, and the 12 is it’s atomic mass)
This isotope has 6 neutrons
C-14 (atomic mass 14) is used for carbon dating and has 8 neutrons!

8. More about Isotopes
In an isotope, the number of protons and electrons never changes- only the number of neutrons is different
This means that each isotope of a particular element has a different atomic mass than another isotope of the same element
Remember: C-12 has an atomic mass of 12 and C-14 has an atomic mass of 14!

9. Count the Number of Protons and Neutrons

10. Quick Activity
Calculate the number of neutrons there are in the following isotopes (use your periodic table to find the atomic numbers)
Carbon-14
Nitrogen-15
Sulfur-35
Calcium-45
Iodine-131