Advertisements
Advertisements
प्रश्न
Find the wavelength of the radiation emitted by hydrogen in the transitions (a) n = 3 to n= 2, (b) n = 5 to n = 4 and (c) n = 10 to n = 9.
उत्तर
From Balmer empirical formula, the wavelength `(lamda)` of the radiation is given by
`1/lamda = R (1/(n_1^2) - 1/n_2^2)`
Here, R = Rydberg constant = `1.097 xx 10^7 m^-1`
n1 = Quantum number of final state
n2 = Quantum number of initial state
(a)
For transition from n = 3 to n = 2:
Here,
n1 = 2
n2 = 3
`1/lamda = 1.09737xx10^7xx (1/4 - 1/9)`
`rArr lamda = 36/(5xx1.0973xx10^7`
`= 6.56 xx 10^-7 = 656 nm`
(b)
For transition from n = 5 to n = 4:
Here,
n1 = 4
n2 = 5
`1/lamda = 1.09737 xx 10^-7 (1/16 - 1/25)`
`rArr = 400/(1.09737xx10^7xx9)`
= 4050 nm
(c)
For transition from n = 10 to n = 9:
Here,
n1 = 9
n2 = 10
`1/lamda = 1.09737 xx 10^7 (1/81 - 1/100)`
`lamda = (81xx100)/(19xx1.09737xx10^7)`
= 38849 nm
APPEARS IN
संबंधित प्रश्न
State Bohr’s third postulate for hydrogen (H2) atom. Derive Bohr’s formula for the wave number. Obtain expressions for longest and shortest wavelength of spectral lines in ultraviolet region for hydrogen atom
Draw a neat, labelled energy level diagram for H atom showing the transitions. Explain the series of spectral lines for H atom, whose fixed inner orbit numbers are 3 and 4 respectively.
State Bohr's postulate to define stable orbits in the hydrogen atom. How does de Broglie's hypothesis explain the stability of these orbits?
State Bohr postulate of hydrogen atom that gives the relationship for the frequency of emitted photon in a transition.
Using Bohr’s postulates, obtain the expressions for (i) kinetic energy and (ii) potential energy of the electron in stationary state of hydrogen atom.
Draw the energy level diagram showing how the transitions between energy levels result in the appearance of Lymann Series.
Evaluate Rydberg constant by putting the values of the fundamental constants in its expression.
A parallel beam of light of wavelength 100 nm passes through a sample of atomic hydrogen gas in ground state. (a) Assume that when a photon supplies some of its energy to a hydrogen atom, the rest of the energy appears as another photon. Neglecting the light emitted by the excited hydrogen atoms in the direction of the incident beam, what wavelengths may be observed in the transmitted beam? (b) A radiation detector is placed near the gas to detect radiation coming perpendicular to the incident beam. Find the wavelengths of radiation that may be detected by the detector.
Obtain Bohr’s quantisation condition for angular momentum of electron orbiting in nth orbit in hydrogen atom on the basis of the wave picture of an electron using de Broglie hypothesis.
In which of the following systems will the wavelength corresponding to n = 2 to n = 1 be minimum?
According to Bohr's theory, an electron can move only in those orbits for which its angular momentum is integral multiple of ____________.
The spectral line obtained when an electron jumps from n = 5 to n = 2 level in hydrogen atom belongs to the ____________ series.
The radius of the third Bohr orbit for hydrogen atom is ____________.
According to Bohr’s theory, the angular momentum of an electron in 5th orbit is ______.
Calculate the energy and frequency of the radiation emitted when an electron jumps from n = 3 to n = 2 in a hydrogen atom.
On the basis of Bohr's model, the approximate radius of Li++ ion in its ground state ifthe Bohr radius is a0 = 53 pm :
According to Bhor' s theory the moment of momentum of an electron revolving in second orbit of hydrogen atom will be.
For the ground state, the electron in the H-atom has an angular momentum = h, according to the simple Bohr model. Angular momentum is a vector and hence there will be infinitely many orbits with the vector pointing in all possible directions. In actuality, this is not true ______.
A hydrogen atom in its first excited state absorbs a photon of energy x × 10-2 eV and exited to a higher energy state where the potential energy of electron is -1.08 eV. The value of x is ______.
The first ionization energy of H is 21.79 × 10-19 J. The second ionization energy of He atom is ______ × 10-19J.
In Bohr's theory of hydrogen atom, the electron jumps from higher orbit n to lower orbit p. The wavelength will be minimum for the transition ______.
