Question

Which of the following are considered a pure substance? Select all that apply.

A) element
B) compound
C) mixture
D) none of the above

Answer 1

An element and a compound are both considered pure substances because they cannot be broken down into simpler substances and have consistent properties. A mixture is not a pure substance as it involves a combination of different substances that are not chemically bonded.

Step-by-step explanation:

In chemistry, we classify substances based on their composition. Among the options provided, both an element and a compound are considered pure substances. An element is a substance that cannot be broken down into simpler substances by chemical means. A compound is a substance that can be broken down into two or more elements and has a constant composition and properties throughout. In contrast, a mixture is a combination of two or more substances that are not chemically combined and can be heterogeneous or homogeneous depending on whether their composition is uniform.