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When you perform this reaction, what could remain at the end of the reaction? check all that apply. excess reactant aqueous copper chloride excess reactant aluminum oxygen product solid copper carbon dioxide product aqueous aluminum chloride water

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?

Which best describes eras and periods?