At is the chemical symbol of astatine.
At is a radioactive halogen that is itself the byproduct of the decay of more massive radioactive atoms. It has a very short half life, and the "world supply" of astatine (the amount believed to exist at any particular moment anywhere in the entire mass of the planet) is about one ounce (approx. 30 grams).
Sn stands for the element tin in the periodic table.
11 is the atomic number for the element sodium in the periodic table.
Calcium.
cerium
iron
N stands for Nitrogen on the periodic table.
Beryilium
there is no such element
iodine
iodine
Sn stands for the element tin in the periodic table.
No, the symbol "H" stands for Hydrogen on the periodic table. The symbol "He" stands for Helium on the periodic table.
Argon is what Ar stands for on the Periodic Table of elements.
potassium
it is fluorine
Beryllium (Be)
Calcium.