Advertisements
Advertisements
प्रश्न
The ground state energy of hydrogen atoms is -13.6 eV. The photon emitted during the transition of electron from n = 3 to n = 1 unknown work function. The photoelectrons are emitted from the material with a maximum kinetic energy of 9 eV. Calculate the threshold wavelength of the material used.
उत्तर
For a transition from n = 3 to n = 1 state, the energy of the emitted photon,
hv = E2 – E1 = `13.6[1/1^2 - 1/3^2]` eV = 12.1 eV.
From Einstein’s photoelectric equation,
hv + Kmax + W0
∴ W0 = hv – Kmax = 12.1 – 9 = 3.1 eV
Threshold wavelength,
λth = `("hc")/"W"_0`
= `(6.62 xx 10^-34 xx 3 xx 10^8)/(3.1 xx 1.6 xx 10^-19)`
= 4 × 10–7m
APPEARS IN
संबंधित प्रश्न
If the velocity of the electron in Bohr’s first orbit is 2.19 × 106 ms-1, calculate the de Broglie wavelength associated with it.
Using Bohr’s postulates, obtain the expression for the total energy of the electron in the stationary states of the hydrogen atom. Hence draw the energy level diagram showing how the line spectra corresponding to Balmer series occur due to transition between energy levels.
Draw energy level diagram for a hydrogen atom, showing the first four energy levels corresponding to n=1, 2, 3 and 4. Show transitions responsible for:
(i) Absorption spectrum of Lyman series.
(ii) The emission spectrum of the Balmer series.
Answer the following question.
Calculate the de-Broglie wavelength associated with the electron revolving in the first excited state of the hydrogen atom. The ground state energy of the hydrogen atom is – 13.6 eV.
The spectral line obtained when an electron jumps from n = 5 to n = 2 level in hydrogen atom belongs to the ____________ series.
In Bohr model of hydrogen atom, which of the following is quantised?
According to Bhor' s theory the moment of momentum of an electron revolving in second orbit of hydrogen atom will be.
The first ionization energy of H is 21.79 × 10-19 J. The second ionization energy of He atom is ______ × 10-19J.
A hydrogen atom in is ground state absorbs 10.2 eV of energy. The angular momentum of electron of the hydrogen atom will increase by the value of ______.
(Given, Planck's constant = 6.6 × 10-34 Js)
In hydrogen atom, transition from the state n = 6 to n = 1 results in ultraviolet radiation. Infrared radiation will be obtained in the transition ______.
