(Given the value of Bohr radius = 0.53 Å) (Compt. ![]() (b) orbital radius in the first excited state of the atom. (i) Find the energy required to move an electron from the ground state to the first excited state of the atom. Ques: The value of a ground state energy of a hydrogen atom is -13.6 eV. \(mvr = \frac\) ….(i)Īlso, according to Bohr’s postulates, the centripetal force is equal to the electrostatic force between the electron and nucleus. To derive an expression for radii of Bohr’s stationary orbits-Īccording to Bohr’s postulates, the angular momentum of electron for any permitted orbit is, The difference in the total energy of electrons in the two permitted orbits is absorbed when the electron jumps from inner to outer orbit and emitted when the electron jumps from outer to inner orbit. (iii) The radiation of energy occurs only when an electron jumps from one permitted orbit to another. Wavelength of the emmited light (electromagnetic rediation) in the vacuum R Rydberg Constant (1.097x 107 m-1) Z Number of proton in the nucleus of the element nf Principal quantum number of final state ni Principal quantum number of the initial state. Total angular momentum of the revolving electron in an integral multiple of h/2π. (ii) Electron can resolve only in certain discrete non-radiating orbits, called stationary orbit. The centripetal force required for revolution is provided by the electrostatic force of attraction between the electron and the nucleus. A suitable number of electrons revolve around the nucleus in circular orbit. (i) Every atom consists of a central core called nucleus in which entire positive charge and mass of the atom are concentrated. The wavelengths of the Lyman series are all in the Ultraviolet band.Īns: Basic postulates of Bohr’s atomic model: According to Bohr's model, when electrons transition takes place from higher energy states (nh=2,3,4,5,6.) to nl=1 energy state, the Lyman series appears. As a result, these series are named after him. The series was discovered by Theodore Lyman during the years 19. R is the Rydberg constant which has a value of 1.09737107 m -1 The energy difference between the various levels of Bohr's model and the wavelengths of absorbed or emitted photons is represented by the Rydberg formula. The Rydberg formula is used to calculate the wavelengths of the spectral series. ![]() These spectral lines are the result of Neils Bohr's model of electron transitions between energy levels. The electrons in the gas make transitions between energy levels once they reach the excited state. This spectrum is made up of numerous different spectral series. The emission spectrum is displayed by the atomic hydrogen.
0 Comments
Leave a Reply. |