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Radioactive Decay: Specific Activity A
specific
The
specific activity A
specific
(Bq.kg-1
) of a radioactive source of mass m containing a
single radionuclide of activity A is given by:
A
Using the decay constant λ, the specific activity A
specific
for a pure radionuclide can be
calculated by:
m
A
specific
=
M
N
T
2ln
M
N
A
A
2/1
A
specific
= λ=
where N
A
is the Avogadro constant and M is the molar mass of the radionuclide:
N
A
= 6.0221367 10
23
mol
-1