Helium glows pale yellow when excited by an electric current. This happens because the electrons in the helium atoms absorb energy from the current and jump to higher energy levels. When they return to their original state, they release the energy as light, which we see as a pale yellow glow.
This is the same principle behind neon signs, which use different gases to create various colors.
Here are some examples of how helium is used to create light:
- Helium-neon lasers: These lasers use a mixture of helium and neon gas to produce a red beam of light.
- Spectroscopy: Scientists use helium to analyze the composition of materials by observing the specific colors of light emitted when helium gas is excited.
