in dire need.
life or death situation.

If you want to create an electrical current, which situation would produce a solution capable of this

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?

How many grams of sodium chloride are in 250ml of a 2.5m naci solution