You bought a loaf of bread at the grocery store. When you got home it was approximately half the size it was in the store because the carryout did not sack your groceries properly! Ugh! Compare & contrast the density,
mass, and volume of the original loaf to the "smooshed" loaf. Be specific!

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?