no, it is most commonly found as a compound
Astatine is produced by nuclear reactions.
hydrogen is most commonly found as a part of water with oxygen.
Astatine is similar to the halogen family
In the Earth's atmosphere.
Oxygen, hydrogen, halogens
Very probable this element is oxygen.
Oxygen, hydrogen, halogens
Polonium doesn't contain another element.
Polonium doesn't contain another element.
I think it is hydrogen
Because it's the most simple.
Roentgenium is an artificial chemical element.