If atoms are made of smaller parts such as electrons, why are atoms considered the basic unit of matter?

xd

Firstly, atoms are also composed of protons and neutrons as well as electrons.

Now, to answer your question... Atoms are the smallest you can go while still having it be an element, hence the definition ''the basic unit of a chemical element.'' It is the smallest unit that has the chemical properties of an element. However, atoms still need these charges to be atoms. Without electrons, they'd just be ions. Hope this helps.