Which is the most accurate description of compounds? a. they are formed by elements that join in any given mass ratio. b. they have the same properties as the elements that make them up. c. they have a unique set of properties that can be used as identifiers. d. they cannot be broken down into the elements that form them through chemical changes.

c.They have a unique set of properties that can be used as identifiers.

Explanation:

Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.

Compounds can be decomposed into simpler constituents using chemical reactions.

Example: Water

Compounds have different properties than the elements it is made up of.

Thus the most accurate description of compounds is that they have a unique set of properties that can be used as identifiers.