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Understanding Radiation:
Atomic Shorthand
(Representing Atomic Properties)
Radiation and Radioactivity
As scientists identified the nuclear properties of elements and found different forms of elements, they needed an easy way to write and keep track of the basic nuclear properties. They developed a 'shorthand' that combines the defining pieces of information about the various forms of an element:
- chemical symbol of the element, for example, "C" for carbon
- number of protons in the nucleus (Z) ( the same for any form of an element),
- mass of one atom of the element (A).
The number of neutrons in the nucleus is equal to A - Z.
(A, the atomic mass, is sometimes placed on the left above the Z.)
For example, two different forms, or isotopes, of carbon are:
- carbon, which has 6 protons and 6 neutrons, or an atomic mass of 12. This is the most common form of carbon.
- carbon having 6 protons and 8 neutrons. This form of carbon is radioactive and used in determining the age of archeological artifacts.
You will frequently see these forms of carbon referred to as "Carbon-12" and "Carbon-14."
