Memory Game The atom & periodic table Online version Match the pairs! by Nikita Fitzpatrick Thomson used this device to determine that cathode rays have a - charge The spectrum gained when light is emitted through electron movement down levels William Crookes used this to help to discover cathode rays Put forward a theory for the atom based on the element hydrogen The spectrum gained when light is absorbed This experiment helped to discover the mass to charge of an electron A image taken in the same region of light as the Paschen series George Stoney gave this a name.....