a) Calculate the radius of the orbit, the velocity of the electron and the energy for the ground state and first two excited states according to the Bohr model for H atom.

b) Use a schematic energy diagram for the Bohr model of a H-atom (energy as a function of state) to explain the process of ionization from the ground state.

c) Calculate the ionization energy of a H-atom.

d) What is the wavelength of a photon that ionizes a H atom?