If a substance is composed entirely of one type of atom, it is known as a(n) _______.

Question

anonymous · Answer

Welcome to Open Study - the idea is to help you answer questions so let me direct you to a page where you might find the answer: http://en.wikipedia.org/wiki/Chemical_element Best wishes,

anonymous · Answer

This is not the answer to the question , wiki will fill in the gaps but only hydrogen has one atom and the words proton and hydrogen are interchangeable .

Remember most of us are undergrads and our answers should be questioned as they may be wrong and there will  almost always be more layers of complexity underneath them .

anonymous · Answer

Might I suggest that an element IS a substance entiirely composed of one atom. Biokid is correct that hydrogen is an element in which each atom is made up of one proton and one electron; however there are many types of atoms. I hope this clears up any confusion, best wishes

anonymous · Answer

ebaxter's right. It's called a "chemical element."