Question

You have a substance and begin a set of experiments in which you break it down into other substances through chemical reactions. after a few successive reactions, you discover a set of products that can't be broken down further, no matter what type of chemical reaction you attempt. these substances are:

Answer 1

They're elements. Elements are the simplest form of any substance that cannot be broken down by any chemical methods, including electrolysis or even heat. Examples include oxygen, hydrogen etc.