Answer:
Joseph John Thomson studied the properties and the effects of the cathodic rays. Thomson's experiments involved the passage of electricity through a high-vacuum cathode-ray tube composed by a positive electrode (anode) and a negatively charged cathode. This experiment was crucial to describe the nature of the electric discharge.
Step-by-step explanation:
Michael Faraday placed two electrodes in water solution and then he observed how electricity forces can separate elements in the solution.
William Crookes studied the forces that drive electricity phenomena by passing electricity through a gas in a sealed tube (cathode ray tubes).
Wilhelm Roentgen discovered the electromagnetic radiation in the X-ray spectrum
Finally, Ernest Rutherford was an apprentice of JJ Thompson. He designed an experiment involving alpha particles that were emitted by a radioactive element. This experiment showed that atoms have tiny and heavy nucleus.