Is Energy Conserved When an Atom Emits a Photon?

Electrons can move from one level to another, but the atom's total energy must always be conserved. So, if an electron moves down from the 2nd energy level to the 1st (n=2 to n=1), then the atom conserves energy by emitting a photon of light.

When an atom emits a photon what happens?

When an atom emits a photon, the atom loses the amount of energy the photon carries off. Since atoms can only have certain energies, they can only emit photons of certain energies. The photon energy must equal the different between two allowed amounts of atom energy.

Is photon conserved?

However the number of photons is not conserved. Photons are bosons and they are their own antiparticle so no particle number conservation law is violated when you create a photon.

Maya Lin-Takahashi

Maya Lin-Takahashi

Consumer Tech & Gadget Reviewer

Maya is a hardware enthusiast who tests and reviews smart home devices, smartphones, wearables, and audio gear. She focuses on practical consumer value and build quality.