I need help with this question please. Full answer for good rating. The Bohr mod
ID: 2075681 • Letter: I
Question
I need help with this question please. Full answer for good rating.
The Bohr model postulates that electrons occupy circular orbits around the proton at the nucleus of the hydrogen atom, and do not radiate continuously (as required in classical electromagnetic theory). Bohr further postulated that the electron gained or lost energy by absorbing or emitting a photon of frequency (f) and, in doing so, jumped from one stationary state (orbit of radius r_1) to another stationary state (orbit of radius r_2). Since, in each stationary state, the electron-proton system has a specific total energy E(r), Bohr was assuming that: hf = |E(r_2) - E(r_1)| Explain in your own words what this expression means. Consider the following questions in your response: What motivates its introduction (i.e., what is the connection to Einstein's conclusions based on the photoelectric effect? Would the energy emitted or absorbed in the jumps have any direct relation to the orbital frequency of the electrons motion? Why have the absolute value (magnitude) signs? Under what conditions would the right hand side of the equation be positive and under what conditions would it be negative?Explanation / Answer
The equation means that the difference in the energy of the electron in two different orbits is hf. If an electron jumps down from the orbit r2 to orbit r1 where r2>r1 then the elctron emits energy as photon- having a frequency of f Hz. If it jumps up to r2 from r1 then in order to do that it has to absorb energy hf which will be supplied by the incident photons. E(r) represents the energy of orbit as a function of r.
As the loosely bounded conduction electrons are trapped on the metal lattice, in order to be free they need additional energy. This energy comes in terms of incident photon. As the energy of the photon only depends on its frequency, thus for a certain frequency photoelectic emmission or liberation of electrons from the metal surface starts. This is the motivation of photoelectric effect.
The orbital frequencies are equal to the frequency of the emmited photons.
The absolute value signs are the reminder that the total energy difference is either radiative or absorptive. When jumping from a higher energy orbital to a lower energy orbit the electron emits energy, thus it is positive. When the jump is made from a lower energy to higher energy orbit the energy becomes negative, i.e absorptive, it has to absorb energy in terms of incident photon to make that jump.