1. Nuclear Chemistry and Radioactivity
CHAPTER 20
Nuclear Chemistry and Radioactivity
20.1 Nuclear Equations

2. So far, we have only looked at reactions involving the outer electrons
neutrons
protons
electrons
So far, we have only looked at reactions involving the outer electrons

3. neutrons
protons
electrons
Chemical reactions rearrange elements into new compounds, leaving the elements unchanged
Chemical equations

4. Nuclear reactions create new elements from other elements
electrons
protons
neutrons
Chemical reactions rearrange elements into new compounds, leaving the elements unchanged
Nuclear reactions create new elements from other elements
Nuclear equations
Chemical equations

5. Representing nuclei
In nuclear equations we need to keep track of the number of neutrons and the number of protons
protons
neutrons

6. Representing nuclei
In nuclear equations we need to keep track of the number of neutrons and the number of protons
2 protons + 2 neutrons
2 protons
element symbol

7. The periodic table gives you the number of protons
In a nuclear reaction, uranium disintegrates
into thorium and helium
The periodic table gives you the number of protons

8. Like in a chemical equation, a nuclear equation must be balanced
Mass number balance (protons + neutrons) =
1) There must be mass number balance

9. Like in a chemical equation, a nuclear equation must be balanced
Mass number balance (protons + neutrons) =
1) There must be mass number balance
2) There must be charge conservation
Charge balance (protons) =

10. Nuclear reactions create new elements from other elements
protons
neutrons
In a nuclear equation, there must be:
1) mass number balance
2) charge conservation