Radiactive Decay

Question 1

What nuclei are referred to as radioactive?

Answer 1

Unstable nuclei are radioactive.

Question 2

What could instability of a nucleus be caused by?

Answer 2

Unstable nuclei could be caused by
- too many neutrons
- too few neutrons
- too many nucleons (too heavy)
- too much energy in the nucleus

Question 3

How does a nucleus decay?

Answer 3

A nucleus decays by radioactive decay.
This is when a nucleus decays by releasing energy/particles until it reaches a stable form.

Question 4

What are the 4 types of radiation?

Answer 4

Alpha - α - helium nucleus - 2 protons, 2 neutrons, +2 charge
Beta-minus - β, β- - electron
Beta-plus - β+ - positron
Gamma - Γ - short wavelength, high frequency EM wave

Question 5

What are the properties of alpha radiation?

Answer 5

Alpha has a:
- strong ionising ability
- slow speed
- Absorbed by paper or few cm of air

Question 6

What are the properties of a beta-minus?

Answer 6

Beta minus has a:
- Weak ionising ability
- Fast speed
- Absorbed by thin sheet of aluminium