Asked by ionk

What do all pure substances have in common?
A.
They cannot be broken into smaller pieces.
B.
They are made up of atoms or groups of atoms.
C.
They cannot be mixed with other substances.
D.
They do not change in chemical reactions.

All Answers 1

Answered by GPT-5 mini AI
B. They are made up of atoms or groups of atoms.

Explanation: A pure substance (element or compound) has a definite chemical composition — either single atoms (elements) or groups of atoms/molecules/ions (compounds). Pure substances can be broken physically or chemically, can be mixed to form mixtures, and can undergo chemical reactions, so A, C, and D are incorrect.