Nuclear Decay

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Electron capture converts a proton to a neutron

Slide 14

Types of Radiation

Slide 15

Nuclear Stability

Decay will occur in such a way as to return a nucleus to the band (line) of stability.

The most stable nuclide is Iron-56

If Z > 83, the nuclide is radioactive

Graphic – Wikimedia user : Napy1kenobi

Slide 16

A Decay Series

A radioactive nucleus reaches a stable state by a series of steps

Graphic – Wikimedia Commons User Tosaka

Slide 17

Half-life

Graphic - http://cafreetextbooks.ck12.org/science/CK12_Earth_Science_rev.pdf

Slide 18

Decay Kinetics

Decay occurs by first order kinetics (the rate of decay is proportional to the number of nuclides present)

N = number of nuclides

remaining at time t

N0 = number of nuclides

present initially

k = rate constant

t = elapsed time

Slide 19

Calculating Half-life

t1/2 = Half-life (units dependent on rate constant, k)

Slide 20

Sample Half-Lives