How do neon lights work

We say the gas discharges under these conditions, meaning that it can conduct, i.e. an electric current can flow through it. 

Collisions involving the mobile electrons are generally elastic. They bounce, like a ball off a wall. But a tiny fraction of the electrons undergo an inelastic collision with un-ionized neon atoms, causing a fraction of the electron s internal energy to transfer to the neon atom. The electron subsequently moves away after the collision. It has less energy, and so is slower. 

The excited-state neon atom is denoted with an asterisk, as Ne.  

When we look closely at a neon lamp, we should see that it is the gas itself that emits the light, and not the electrodes. 

The reaction in Equation (9.25) occurs in the gas phase, but the (9) subscripts have been removed for clarity. 

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