Radioactivity and Half-Life

CH 38

Include water waves and sound

Waves in media

Variations of protons, neutrons and electrons emitted at high speed from radioactive atoms

Particles (Particulate)

Double-waves propagated in   magnetic and electrical fields, including light, ultraviolet, infrared, microwaves, radio and TV

Electromagnetic

Number of protons in the nucleus

Atomic Number (Z)

Total number of nucleons in the nucleus (Protons+neutrons)

Atomic mass (A)

Spontaneous emission of radiation (particles or photons) from atoms

Radioactivity

Alpha emission does what to the Z and A number

Decreases Z by 2

Decreases A by 4

Which has more mass alpha or beta

Alpha

What does beta emission do to the Z and A number

Increases Z by 1

Doesnt change A

What does gamma emission do to the Z and A number

Nothing

Alpha particles with a charge of +2 do what to electrons

Pull them out of their orbit

Beta particles with a charge of -1 do what to electronics

Repel them out of their orbit

Penetration is __ related to biological harm

Inversely

Which penetrates more? Gamma rays or xrays

Gamma

Beta particles have __ the mass of alpha particles

1/8000th

__ particles penetrate 2cm or less into tissue, making them suitable for treatment of subcutaneous or testicular cancer

Beta

Isomer emits only __ rays

Gamma

Half life is abbreviated by

T1/2

High decay rate and long half-life (More or less harmful)

More

Short half life (more or less harm)

Less

Short half life and low decay rate (more or less harmful)

Less

Any radioactive element

Radionuclide

Although radioactivity declines over time, half-life is __

Constant

Half life will never reach __

0

How many half-lives does it take for a substance to no longer be considered radioactive

10