De Broglie Wavelength Problems 1] A bacterium ( ) in the blood is moving at 0.33 m/s. What is the de Broglie wavelength of this bacterium? 2] How fast does a proton have to be moving in order to have the same de Broglie wavelength as an electron that is moving with a speed of 3] ? A particle has a de Broglie wavelength of . Then its kinetic energy doubles. What is the particle’s new de Broglie wavelength, assuming that relativistic effects can be ignored? Line Spectra and the Bohr Model 1] The electron in a hydrogen atom is in the first excited state, when the electron acquires an additional 2.86 eV of energy. What is the quantum number n of the state into which the electron moves? 2] Using the Bohr model, determine the ratio of the energy of the nth orbit of a triply ionized beryllium atom (Be3+, Z = 4) to the energy of the nth orbit of a hydrogen atom (H). 3] A singly ionized helium atom (He+) has only one electron in orbit about the nucleus. What is the radius of the ion when it is in the second excited state? 4] (a) What is the minimum energy (in electron volts) that is required to remove the electron from the ground state of a singly ionized helium atom (He+, Z = 2)? (b) What is the ionization energy for He+? 5] A hydrogen atom is in the ground state. It absorbs energy and makes a transition to the n = 3 excited state. The atom returns to the ground state by emitting two photons. What are their wavelengths? 6] In the hydrogen atom the radius of orbit B is sixteen times greater than the radius of orbit A. The total energy of the electron in orbit A is −3.40 eV. What is the total energy of the electron in orbit B? 7] The energy of the n = 2 Bohr orbit is −30.6 eV for an unidentified ionized atom in which only one electron moves about the nucleus. What is the radius of the n = 5 orbit for this species?