The negatively charged particles that move easily through materials are electrons.

Here's why:

* Electrons are the smallest and lightest charged particles in atoms. This makes them relatively easy to move around compared to protons, which are much larger and heavier.

* Electrons are bound less tightly to the atom than protons. While protons reside in the nucleus of an atom, electrons orbit around the nucleus. This weaker binding allows them to be easily dislodged from their atoms and move freely.

Materials where electrons move easily are called conductors. Examples of conductors include metals like copper and silver.

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