When a hydrogen ($H_2$) lamp is subject to a high voltage hydrogen atoms release energy in the form of light. Somehow $H_2$ is splitted. But...
- Why high voltage produce the dissociation? Does electrons travel through the gas from one electrode to the other one (as electric discharge suggest)? So is $H^-$ resposible for the emission?
Here I'm citing the first link:
For example, when a high-voltage electrical discharge is passed through a sample of hydrogen gas at low pressure, the resulting individual isolated hydrogen atoms caused by the dissociation of H2 emit a red light.