Only answer 19

19. A wavelength of 4.653 um is observed in a hydrogen spectrum for a transition that ends in the nf=5 level. What was ni for the initial level of the electron? 21. A beryllium ion with a single electron (denoted Be3+) is in an excited state with radius the same a of the ground state of hydrogen. (a) What is n for the Be3+ ion? R=(N^2/z)a0 R=a0 AO=(ng/4120