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Einsteinium Symbol Es Atomic Number 99 Atomic Mass 252.0828 Family Actinide Transuranium Element Pronunciation ein-STY-nee-um Overview Einsteinium is a member of the actinide family. The actinide elements are found in Row 7 of the periodic table, a...

Einsteinium is a transuranium element, located in Row 7 of the periodic table. The elements that make up this family are also known as the actinides, after the first member of the family. Einsteinium's atomic number is 99, its atomic mass is 252.0828,...

Einsteinium is an actinide series, manmade, transuranic element denoted by the atomic symbol Es. Its atomic number is 99 and the average atomic weight of its most stable isotope is 252. It is a radioactive material which has fourteen known isotopes....

Einsteinium (pronounced /aɪnˈstaɪniəm/) is a synthetic element. On the periodic table, it is represented by the symbol Es and atomic number 99. It is the seventh transuranic element, and seventh in the series of Actinides. It was named in honor of...