Last electron is 5

B) A neutron (mass = 1.675 x 10 kg) traveling with a velocity of 911", has a deBroglie wavelength identical to the wavelength of a photon absorbed by an electron on a hydrogen atom at energy level n 2. The energy level, nina, into which the electron is moved is the same as the principal quantum number of the last electron on element X. B) A neutron (mass = 1.675 x 10 kg) traveling with a velocity of 911", has a deBroglie wavelength identical to the wavelength of a photon absorbed by an electron on a hydrogen atom at energy level n 2. The energy level, nina, into which the electron is moved is the same as the principal quantum number of the last electron on element X