this is a slide about the radioactivity of atoms. Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay, beta decay, and gamma decay, all of which involve emitting one or more particles or photons.

1. What is radioactive decay?
• Process where the nucleus of an unstable atom loses energy by
emitting ionizing particles and emits radiation

2. Types of radiation

3. Alpha decay
• Occurs when the nucleus ejects an alpha particle(helium nucleus)
• This could barely pass a single sheet of paper.
• Deflected as a positive particle in a magnetic field.

4. Alpha decay

5. Beta decay
• Is the emission of beta particle or electron,by a radioactive nucleus.
• This can pass through about a 3mm aluminium.
• Deflected as a negative particle in a magnetic field.

6. Beta decay

7. Gamma decay
• Is the release of energy in the form of high frequency electro
magnetic waves.
• This can pass through several centimeters of lead.
• No deflection in a magnetic field.

8. Gamma decay

9. Half life and radioactive decay law
• Radioactivity is a random event we don’t know which atom will decay
at what time but can use probability and statistics to tell us how many
of the atoms will decay in a certain period.
• The equation to determine how much will decay is

10. Radioactive decay law
• The previous equation can be rearranged to find the number of atoms
left after a specific amount of time to decay.
The number of decay per second is called the activity of the sample
To signify how fast the isotope decays HALF LIFE is used.
The half life of an isotope is the time it takes half of the original sample
to decay.

11. Half life
• The half lifes of known radioactive isotopes vary from 10−22 to 1028
seconds (about 10 years).
• Most tables and charts show half life as 𝑇1/2
• The half life and decay constant have an inverse relationship to one
another. The longer the half life the slower the decay constant.
• The precise relationship is

12. Decay of Carbon-14