Exercise 1

According to Bohr’s atomic model, the circumference of the electron orbit is always an _____ multiple of de Broglie wavelength.

Why would any energy be released if electrons are exchanged with Same energy levels?

State Bohr’s postulate to define stable orbits in hydrogen atom. How does de Broglie’s hypothesis explain the stability of these orbits ?

At what speed must have electron revolve around the nucleus of hydrogen atom so that it may not be pulled into the nucleus by electrostatic force of attraction $r=0.5\times {10}^{-10}m, Me=9.1\times {10}^{-31}kg and e=1.6\times {10}^{-19}C$

The electron in a hydrogen atom passes from $n=4$ energy level to $n=1$ energy level. What is the maximum number of photons that can be emitted?

Radius of the smallest orbit of hydrogen atom is

$(h =Planks\text{'} cons\tan t = 6.6\times {10}^{-34}Js, Me=9.1\times {10}^{-31}g \mathrm{and} e=1.6\times {10}^{-19}C)$

A hydrogen atom initially in the ground state absorbs a photon which excites it to the $n=4$ level. Estimate the frequency of the photon.$(R=1.097\times {10}^7 {\mathrm{m}}^{-1})$

The ratio of magnetic field produced by an electron revolving in first orbit of ${\mathrm{He}}^{+}$ atom to that of the $1^{\mathrm{st}}$ orbit of ${\mathrm{Li}}^{++}$ atom is