Step-by-step explanation:
An element is a distinct substance that cannot be split-up into simpler substances. Such substances are only made up of one kind of atom.
A compound is composed of two or more kinds of atoms joined together in a definite grouping.
A homogenous mixture is a mixture in which its constituents exists in just one phase.
A heterogeneous mixture is one whose constituents exists in at least two different phases.
S₈ is a compound
CH₄ is a compound
Salt water is a homogenous mixture
Distilled water is a compound
CH₂O is a compound
Concrete is a heterogenous mixture.