Single Choice

Taking the wavelength of first Balmer line in hydrogen spectrum ($$n=3$$ to $$n=2$$) as $$660nm$$, the wavelength of the 2nd Balmer line ($$n=4$$ to $$n=2$$) will be:

A$$889.2nm$$
B$$642.7nm$$
C$$488.9nm$$
Correct Answer
D$$388.9nm$$

Solution

$$\cfrac { 1 }{ 660 } =R\left( \cfrac { 1 }{ { 2 }^{ 2 } } -\cfrac { 1 }{ { 3 }^{ 2 } } \right) =\cfrac { 5R }{ 36 } ....(1)\quad $$
$$\cfrac { 1 }{ \lambda } =R\left( \cfrac { 1 }{ { 2 }^{ 2 } } -\cfrac { 1 }{ { 4 }^{ 2 } } \right) =\cfrac { 3R }{ 16 } ....(2)\quad \quad $$
dividing (1) with (2)
$$\cfrac { \lambda }{ 660 } =\cfrac { 5\times 16 }{ 36\times 3 } $$
$$\lambda =\cfrac { 4400 }{ 9 } =488.88=488.9nm$$

SIMILAR QUESTIONS

Nuclear Physics

The transition from the state $$n = 4$$ to $$n = 3$$ in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from

Nuclear Physics

Hydrogen atom is excited from ground state to another state with principal quantum number equal to $$4$$. Then the number of spectral lines in the emission spectra will be.

Nuclear Physics

The transition from the state $$n=3$$ to $$n=1$$ in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from-

Nuclear Physics

The energy of the em waves is of the order of 15 keV. To which part of the spectrum does it belong?

Nuclear Physics

Electromagnetic waves of wavelength ranging from $$100\overset {\circ}{A}$$ to $$400 \overset {\circ}{A}$$ comes under :

Nuclear Physics

When an electron jumps from higher orbit to the second orbit in hydrogen, the radiation emitted out will be in $$(R=1.09\times 10^{7}m^{-1})$$

Nuclear Physics

There are only three hydrogen atoms in a discharge tube. The analysis of spectrum shows that in all the hydrogen atoms, electrons are de-exciting from the fourth orbit. What should be the maximum number of spectral lines?

Nuclear Physics

The first line of the sharp series of atomic cesium is a doublet with wavelengths $$1358.8$$ and $$1469.5\,nm$$. Find the frequency intervals (in rad/s units) between the components of the sequent lines of that series.

Nuclear Physics

An atom possessing the total angular momentum $$h\sqrt{6} $$ is in the state with spin quantum number $$S = 1$$. In the corresponding vector model the angle between the spin momentum and the total angular momentum is $$ \theta = 73.2^{\circ} $$. Write the spectral symbol for the term of that state.

Nuclear Physics

Write the spectral symbols for the terms of a two-electron system consisting of one p electron and one d electron.

Contact Details