Question

listen
if all the atoms in a molecule of a substance are alike, then the substance is a/an
compound.
solid.
element.
mixture.

Explanation:

An element is a pure substance made up of only one type of atom. A compound has different atoms bonded together, a solid is a state of matter not defined by atom type, and a mixture combines different substances. The description matches the definition of an element.

Answer:

element.