Home
Class 11
CHEMISTRY
According to Bohr's theory , the electro...

According to Bohr's theory , the electronic energy of hydrogen atom in the `n^(th)` Bohr's orbit is given by
`E_(n) = (-21.76 xx 10^(-19))/(n^(2)) J`
Calculate the longest wavelength of electron from the third Bohr's orbit of the `He^(o+)` ion

Text Solution

Verified by Experts

For hydrogen like ion, i.e., `He^(+)`, the relation is :
`E_n = (21.76 xx 10^(-19) Z^2)/(n^2) J` per atom
where Z is atomic number, For `He^+ ,Z = 2`
Energy of `He^(+)` ion in third orbit `(n = 3)`
`E_3 = (21.76 xx 10^(-19) xx 4)/(3^2) J`
Energy required to removed an electron fro third Bohr orbit of `He^+` ion is :
`Delta E = E_(oo) - E_3`
`= 0 - (-(21.76 xx 10^(-19) xx 4)/(9)) J`
`= 9.67 xx 10^(-19) J`
Now, `Delta E = (hc)/(lambda)`
or `lambda = (hc)/(Delta E) = (6.626 xx 10^(-34) xx 3.0 xx 10^8)/(9.67 xx 10^(-19) J)`
`= 2.055 xx 10^(-7) m = 205.5 nm`.
Promotional Banner

Topper's Solved these Questions

  • STRUCTURE OF ATOM

    MODERN PUBLICATION|Exercise PRACTICE PROBLEMS|62 Videos

  • STRUCTURE OF ATOM

    MODERN PUBLICATION|Exercise Conceptual Questions 1|17 Videos

  • STATES OF MATTER : GASES AND LIQUIDS

    MODERN PUBLICATION|Exercise UNIT PRACTICE TEST|13 Videos

  • THERMODYNAMICS

    MODERN PUBLICATION|Exercise Unit Practice Test|12 Videos

Similar Questions

Explore conceptually related problems

According to Bohr's theory , the electronic energy of hydrogen atom is the oth Bohr's orbit is given by E_(n) = (-21.76 xx 10^(-19))/(n^(2)) J Calculate the longest wavelength of electron from the third Bohr's of the He^(Theta) ion

According to Bohr theory, the electronic energy of hydrogen atom in the nth Bohr orbit is given by E_(n)=-(21.76xx10^(-19))/(n^(2))J . Calculate the longest wavelength of light that will be needed to remove an electron from the 2nd orbit of Li^(2+) ions.

According to Bohr's theory,the electronic energy of a atom in the oth orbit is given by E_(n) = (-2.17 xx 10^(-18))/(n^(2)) J Calculate the longest wavelength of light that will be needed in remove an electron the third Bohr orbit of He^(o+)

Determine wavelength of electron in 4th Bohr's orbit

According to Bohr's theory, the electronic energy of H-atom in Bohr's orbit is given by

Frequency of revolution of electron in the n^(th) Bohr's orbit is given by

The potential energy of an electron in the second Bohr's orbit of the He^(+) ion is :-

Period of revolution of electron in the n^(th) bohr's orbit is given by

According to Bohr's theory, the angular momentum of electron in the fifth Bohr orbit is: