1. Lesson 5
Mr. Guerra
By PresenterMedia.com

2. Nuclear Equations
Alpha Decay

3. Types of Radioactive Decay
Alpha Decay
Loss of an -particle (a helium nucleus)
He
4
2
U Th + He
238 234 4
92  90 2

4. Alpha Decay Question

5. Nuclear Equations
Beta Decay

6. Types of Radioactive Decay
Beta Decay
Loss of a -particle (a high energy electron)
0
e
0
−1
 or −1
I Xe e
131 131 0
53  54 + −1

7. Beta Decay Question

8. Nuclear Equations
Positron emission: A positron is a particle
equal in mass to an electron, but with opposite
charge.

9. Types of Radioactive Decay
Positron Emission
Loss of a positron (a particle that has
the same mass as but opposite charge
than an electron)
e
0
1
C B e
11 11 0
6  5 + 1

10. Positron Emission Question

11. Types of Radioactive Decay
Gamma Emission
Loss of a -ray (high-energy radiation
that almost always accompanies the loss of
a nuclear particle)
0
0


12. Types of Radioactive Decay
Gamma ray release
• Gamma ray – high energy photon
– Examples
• Net effect is no change in mass number or atomic
number.

13. Gamma Ray Question

14. Nuclear Equations
Electron capture: A nucleus absorbs an
electron from the inner shell.

15. Types of Radioactive Decay
Electron Capture (K-Capture)
Addition of an electron to a proton in the
nucleus
• As a result, a proton is transformed into a
neutron.
p+ e n
1 0 1
1 −1  0

16. Electron Capture Question

17. Lesson 5 End