9. The elements fluorine, chlorine, and bromine are found to exhibit similar chemical properties. Explain. SECTION 31-4 DE BROGLIE WAVES AND THE BOHR MODEL 35. Find the de Broglie wavelength of an electron in the ground state of the hydrogen atom. 39... What is the radius of the hydrogen-atom Bohr orbit shown in FIGURE 31-40? FIGURE 31-40 Problem 39 SECTION 31-5 THE QUANTUM MECHANICAL HYDROGEN ATOM 0 42. What are the allowed values of/ when the principal quantum number is n = 5? SECTION 31-6 MULTIELECTRON ATOMS AND THE PERIODIC TABLE 51. CE (a) How many electrons can occupy the 3d subshell? (b) How G