yes, element 26 (Fe)
No, it is a naturally occurring element
Astatine
Yes. but it is a very rare naturally occurring element.
No. Lithium is a naturally occurring element.
No, it is a naturally occurring element.
No. Iron is a naturally occurring element.
The average of all the naturally occurring isotopes of a particular element are an element's atomic Mass.
Lead is an element---Go to http://en.wikipedia.org/ and look up lead---Natural or Synthetic is irrelevant when you're talking about elements. (If you don't know what I'm talking about, then maybe you ought to also read the wikipedia article on Chemical Element.)
The heaviest naturally occurring element is uranium, and it has 92 electrons.
Iron is an ore.
No, it is a naturally occurring element
Astatine
We look to the naturally occurring element uranium as a nuclear fuel.
As a naturally occurring metallic mineral it is rare. As an element or component in the chemical composition of rocks and minerals, extremely common.
Naturally occuring.
Yes. but it is a very rare naturally occurring element.
Oxygen is a naturally occurring element.