PLZZZ HELPPP IM DOING A TEST On the periodic table, how is atomic mass
represented?
A. As the mass of the most common isotope
B. As the exact mass of every atom
C. As the masses of all the protons added together
D. As an average of the mass of different isotopes

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?

If one fission reaction of a uranium-235 atom produced two neutrons, how many neutrons would be released if the chain reaction occurred three more times?

What the blanks in these lines are ?