A substance that contains only a single type of atom is

element

Explanation:

Atoms are the building blocks of all matter. When a substance contains only one type of atom, it is called an element. Each element has a special name and unique properties that are different from all the rest of the elements. All known elements are organized on a chart called the periodic table of elements.

An element

Explanation:

An element is a substance consisting the same type of atoms.

there are no statements provided but here is why:

sulfur belongs to group 16 because it can be found in nature whether it is in a free or combined state.

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