Which term describes this reaction? Two central Carbons are double bonded to each other, with H above left and right and below left and right of the pair. An arrow points to an ongoing zig zag chain with C H 2 at each corner.

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?