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Astatine Symbol At Atomic Number 85 Atomic Mass 209.9871 Family Group 17 (Viia) Halogen Pronunciation AS-tuh-teen Overview Astatine is a member of the halogen family, elements in Group 17 (VIIA) of the periodic table. It is one of the rarest elements...

Most students of chemistry study the first four members of the halogen family-- fluorine, chlorine, bromine, and iodine --but hear little or nothing about the last member, astatine. Chemists searched long and hard for this element in nature, but...

Astatine is a member of the halogen family, the elements that make up Group 17 of the periodic table. Its atomic number is 85, its atomic mass is 209.9871, and its chemical symbol is At. All isotopes of astatine are radioactive. They have such short...

Astatine (pronounced /ˈæstətiːn/) is a chemical element with the symbol At and atomic number 85. This radioactive element occurs naturally from uranium-235 and uranium-238 decay. It is the heaviest of the...

Monoclonal antibodies (mAbs) labeled with a-emitting radionuclides such as ^sup 211^At, ^sup 212^Bi, ^sup 213^Bi, and ^sup 212^Pb (which decays by P-emission to its a.-emitting daughter, ^sup 212^Bi) are being evaluated for their potential applications for cancer therapy. The fate of these radionuclides after...