Advertisements
Advertisements
प्रश्न
Calculate the longest wavelength in the Paschen series.
(Given RH =1.097 ×107 m-1)
उत्तर
Given: n = 3, m = 4
To find: Longest wavelength in Paschen series (λL)
Formula: `1/lambda_"L" = "R"[1/"n"^2 - 1/"m"^2]`
Calculation:
From formula,
`1/lambda_"L" = "R"[1/3^2 - 1/4^2]`
∴ `1/lambda_"L" = "R"[1/9 - 1/16]`
= `"R"[(16 - 9)/(9 xx 16)] = (1.097 xx 10^7 xx 7)/(9 xx 16)`
∴ `lambda_"L" = (9 xx 16)/(1.097 xx 7) xx 10^-7`
= antilog {log(9) + log(16) − log(1.097) − log(7)} × 10−7
= antilog{0.9542 + 1.2041 − 0.0402 − 0.8451} × 10−7
= antilog{1.2730} × 10−7
= 18.75 × 10−7 m
∴ λL = 18750 Å
The longest wavelength in the Paschen series is 18750 Å.
संबंधित प्रश्न
Linear momentum of an electron in Bohr orbit of H-atom (principal quantum number n) is proportional to ______.
If aO is the Bohr radius and n is the principal quantum number then, state the relation for the radius of nth orbit of the electron in terms of Bohr radius and principal quantum number.
State any two limitations of Bohr’s model for the hydrogen atoms.
Calculate the shortest wavelength in the Paschen series if the longest wavelength in the Balmar series is 6563 Ao.
How the linear velocity 'v' of an electron in the Bohr orbit is related to its quantum number 'n'?
The radius of electron's second stationary orbit in Bohr's atom is R. The radius of the third orbit will be ______
The ratio of speed of an electron in the ground state in the Bohr's first orbit of hydrogen atom to velocity of light (c) is ____________.
(h = Planck's constant, ε0 = permittivity of free space, e = charge on electron)
For a certain atom when the system moves from 2E level to E, a photon of wavelength `lambda` is emitted. The wavelength of photon produced during its transition from `(4"E")/3` level to E is ____________.
Taking the Bohr radius as a0= 53 pm, the radius of Li++ ion in its ground state, on the basis of Bohr's model, will be about ______.
The total energy of an electron in an atom in an orbit is -3.4 eV. Its kinetic and potential energies are, respectively ______.
In the nth orbit, the energy of an electron `"E"_"n"= -13.6/"n"^2"eV"` for hydrogen atom. The energy required to take the electron from first orbit to second orbit will be ____________.
When hydrogen atom is in its first excited level, its radius is how many time its ground state radius?
The acceleration of electron in the first orbit of hydrogen atom is ______.
Angular speed of an electron in the ground state of hydrogen atom is 4 × 1016 rad/s. What is its angular speed in 4th orbit?
Ratio of centripetal acceleration for an electron revolving in 3rd orbit to 5th orbit of hydrogen atom is ______.
In Bohr model, speed of electron in nth orbit of hydrogen atom is ______. (b = Planck's constant, n = principal quantum number, ∈0 is the permittivity of free space, e = electronic charge)
In Bohr's model of hydrogen atom, which of the following pairs of quantities are quantized?
If a charge on the body is 1 nC, then how many electrons are present on the body?
In hydrogen atom, during the transition of electron from nth outer orbit to first Bohr orbit, a photon of wavelength `lambda` is emitted. The value of 'n' is [R =Rydberg's constant] ____________.
The electron of mass 'm' is rotating in first Bohr orbit of radius 'r' in hydrogen atom. The orbital acceleration of the electron in first orbit is ______.
(b =Planck's constant)
The ground state energy of the hydrogen atom is -13.6 eV. The kinetic and potential energy of the electron in the second excited state is respectively ______
The third line of the Balmer series, in the emission spectrum of the hydrogen atom, is due to the transition from the ______.
The momentum of an electron revolving in nth orbit is given by ______.
The value of Rydberg constant in joule is ______.
The speed of an electron in ground state energy level is 2.6 × 106 ms-1, then its speed in third excited state will be ______.
Let Ee and Ep represent the kinetic energy of electron and photon, respectively. If the de-Broglie wavelength λp of a photon is twice the de-Broglie wavelength λe of an electron, then `E_p/E_e` is ______.
(speed of electron = `c/100`, c = velocity of light)
Find the ratio of radius of 1st Bohr orbit to that of 4th Bohr orbit.
