What was Thomson's significant discovery regarding electrons?

Thomson's significant discovery regarding electrons lies in his experiments with cathode ray tubes, which allowed him to identify and characterize these subatomic particles. By applying a high voltage across the tube, Thomson observed the behavior of cathode rays, which were streams of negatively charged particles that he later named electrons. His work demonstrated that these particles were much smaller than atoms and were negatively charged, fundamentally changing the understanding of atomic structure.

The use of cathode ray tubes was critical as it provided the experimental evidence that electrons exist as discrete particles and could be distinguished from the larger atomic structure. This discovery laid the foundation for modern atomic theory, indicating that atoms are composed of smaller charged particles. This revolutionary understanding contributed to the advancement of chemistry and physics, as it revealed a new layer of complexity in the composition of matter.