Which of the answer choices best describes elements? homogeneous mixtures, always solid, pure substances, very dense.

Option (c) is the correct answer.

Explanation:

An element is defined as the substance that consists of same type of atoms. Also, it can never be broken down or divided into simpler substances.

For example, a sodium metal will contain only atoms of sodium and no other element.

Hence, elements are pure substances because they have only one type of atoms. An element can be present in solid, liquid or gaseous state.

A homogeneous mixture is defined as the mixture that contains even distribution of solute particles into the solvent.

For example, salt in water is a homogeneous mixture.

Thus, we can conclude that pure substances best describes elements.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.