An atomic scientist was studying an atom and through experimentation found that the total negative charge of the area surrounding the nucleus is -9. Which statement correctly describes this atom? A. This atom has nine clouds.
B. This atom has nine electrons.
C. This atom has nine neutrons.
D. This atom has nine protons.

The nuclear potential that binds protons and neutrons in the nucleus of an atom is often approximated by a square well. imagine a proton conned in an innite square well of length 105 nm, a typical nuclear diameter. calculate the wavelength and energy associated with the photon that is emitted when the proton undergoes a transition from the rst excited state (n 2) to the ground state (n 1). in what region of the electromagnetic spectrum does this wavelength belong?