When Faraday was investigating the conductive properties of gases, he sealed metal electrodes into a glass tube and attached an electrostatic generator. When he started the generator, he noticed a purple glow. The purple color was dependant on which of the following?

W) The conductivity of the gas in the tube

X) The type of gas in the tube

Y) The type of metal used for the electrodes

Z) The amount of energy given to the electrodes
X) THE TYPE OF GAS IN THE TUBE