Water and salt are compounds made of the combination of more than one type of atom. Which statement is false?

A. Because they are compounds, they cannot be pure substances.
B. Both compounds are considered pure substances.
C. These compounds have specific physical properties that never
change.
D. These compounds have distinct chemical properties.

Please explain.

A. Because they are compounds, they cannot be pure substances.

Explanation:

The false statement from the given choices is that because they are compounds they cannot be pure substances. In fact, because they are compounds they are pure substances.

Pure substances are made up of elements and compounds and they have the following properties:

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.