210 total combined
Protons/Electrons: 85 Number of Neutrons: 125
As for all other elements: neutrons, protons and electrons.
Astatine has 85 protons.
Astatine, with a molecular weight of 210 amu.
Each isotope has a different number of neutrons. Number of neutrons = Atomic mass of the astatine isotope - 85
Astatine has 125 neutrons
210 total combined
124
Number of neutrons = Mass number - atomic number = 210 - 82 = 128
The atomic mass of astatine is 209.9871 atomic mass units (amu). The atomic mass is given for the longest lived isotope of astatine, which is astatine-210, with a half life of 8.3 hours.
Protons/Electrons: 85 Number of Neutrons: 125
Polonium-210 has 84 protons, 84 electrons and 126 neutrons.
Polonium-210 has 126 neutrons.
The isotope 210Rn has 86 protons and electrons; also 124 neutrons.
As for all other elements: neutrons, protons and electrons.
84 protons, the same as the atomic number, and (210 - 84) or 126 neutrons. The numbers of protons and neutrons together equals the mass number.