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Radiation Protection Glossary

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Atom
Ionactive Hydogen Atom
Ionactive Carbon Atom (C-14)
The constituent of elements - the smallest building block which can combine chemically with other atoms and therefore form compounds.. The atom consists of an electron cloud surrounding a nucleus. The nucleus contains positively charged protons and neutral neutrons, whereas the electron cloud is made up of negatively charged electrons. The number of protons (Z) determines the chemical element and the number of neutrons determines the isotope of the element.