Question

a student hears in chemistry class that a certain object is made of a pure substance. what can the student conclude about the object based on this information?

a. it contains only one type of atom.

b. it can be separated into different components.

c. it always takes the shape of its container.

d. it is made of either an element or a compound.

e. it is a homogeneous mixture.

Explanation:

• Option A: Pure substances can be compounds (which have multiple atom types), so A is wrong.
• Option B: Pure substances have a fixed composition and can't be separated into different components by physical means, so B is wrong.
• Option C: Only liquids and gases (fluids) take the shape of their container; solids (pure substances too) don't, so C is wrong.
• Option D: Pure substances are defined as being either elements (one type of atom) or compounds (two or more types of atoms chemically combined), so this is correct.
• Option E: A homogeneous mixture is a mixture, not a pure substance, so E is wrong.

Answer:

D. It is made of either an element or a compound.