Why do neon signs glow in colors?

Answer: Gas atoms emit specific wavelengths

Heat produces colored light — Wrong. Heat is involved (plasma), but color comes from electrons dropping energy levels in gas atoms, emitting specific wavelengths.

Electricity splits into colors — Wrong. Electricity doesn't split into colors. Electric current excites gas atoms; when electrons return to lower energy levels, they emit specific light wavelengths.

Gas atoms emit specific wavelengths ✓ — Correct! Neon signs contain low-pressure gases (neon, argon, xenon, etc.). Electricity excites gas atoms—electrons jump to higher energy levels. When they drop back, they emit photons of specific wavelengths. Neon emits red-orange (~640nm), helium gives yellow, argon+mercury makes blue. Each element has a unique emission spectrum!