Which statement describes how an atom in the ground state becomes excited?
(1) the atom absorbs energy, and one or more electrons move to a higher electron shell.
(2) the atom absorbs energy, and one or more electrons move to a lower electron shell.
(3) the atom releases energy, and one or more electrons move to a higher electron shell.
(4) the atom releases energy, and one or more electrons move to a lower electron shell.

Using data from seismic waves, geologists have learned that earth’s interior is made up of several

What are the first three quantum numbers for the electrons located in subshell 2s?

Americium-241 undergoes fission to produce three neutrons per fission event. if a neutron-absorbing material is mixed in with this sample so that the rate of neutron production drops down to 1.8 neutrons per fission event, which will be effective at achieving a critical mass? check all that apply. remove a deflective shield surrounding the sample. remove absorbent material mixed in with the sample. compress the sample of americium-241.