Advertisements
Advertisements
प्रश्न
State three postulates of Bohr's theory of hydrogen atom.
उत्तर
Neil Bohr's major three postulates about Bohr's model of the hydrogen atom are:
- Atoms contain a number of stable orbits in which electrons can live without producing energy; each orbit corresponds to a specific amount of energy.
- When an electron jumps from one orbit to another, there is an energy difference equal to E = nhν because the energy of the outer orbit is greater than the energy of the inner orbit.
- The angular momentum of the electron is quantized which can be shown as:
L = `(nh)/(2pi)`, where n = 1, 2, 3, ..........
APPEARS IN
संबंधित प्रश्न
What is the energy in joules, required to shift the electron of the hydrogen atom from the first Bohr orbit to the fifth Bohr orbit and what is the wavelength of the light emitted when the electron returns to the ground state? The ground state electron energy is –2.18 × 10–11 ergs.
On the basis of Bohr's theory, derive an expression for the radius of the nth orbit of an electron of the hydrogen atom.
Balmer series was observed and analysed before the other series. Can you suggest a reason for such an order?
A positive ion having just one electron ejects it if a photon of wavelength 228 Å or less is absorbed by it. Identify the ion.
Radiation coming from transition n = 2 to n = 1 of hydrogen atoms falls on helium ions in n = 1 and n = 2 states. What are the possible transitions of helium ions as they absorbs energy from the radiation?
When a photon is emitted by a hydrogen atom, the photon carries a momentum with it. (a) Calculate the momentum carries by the photon when a hydrogen atom emits light of wavelength 656.3 nm. (b) With what speed does the atom recoil during this transition? Take the mass of the hydrogen atom = 1.67 × 10−27 kg. (c) Find the kinetic energy of recoil of the atom.
Mention demerits of Bohr’s Atomic model.
The energy of an electron in an excited hydrogen atom is - 3.4 eV. Calculate the angular momentum of the electron according to Bohr's theory. (h = 6.626 × 10-34 Js)
According to the Bohr theory of H-atom, the speed of the electron, its energy and the radius of its orbit varies with the principal quantum number n, respectively, as:
The wavelength of the first time line of Ballmer series is 6563 A°. The Rydberg constant for hydrogen is about:-