The magnetic moment $\left(\mathrm{\mu }\right)$ of a revolving electron around the nucleus varies with principal quantum number n as

(1) $\mathrm{\mu }\propto \mathrm{n}$            

(2) $\mathrm{\mu }\propto 1/\mathrm{n}$

(3) $\mathrm{\mu }\propto {\mathrm{n}}^2$           

(4) $\mathrm{\mu }\propto 1/{\mathrm{n}}^2$

Bohr's atom model assumes 

(1) The nucleus is of infinite mass and is at rest

(2) Electrons in a quantized orbit will not radiate energy

(3) Mass of electron remains constant

(4) All the above conditions

Consider a hydrogen like atom whose energy in nth exicited state is given by ${\mathrm{E}}_{\mathrm{n}}=-\frac{13.6 {\mathrm{Z}}^2}{{\mathrm{n}}^2}$ when this excited atom makes a transition from excited state to ground state, most energetic photons have energy ${\mathrm{E}}_{\max }$ = 52.224 eV and least energetic photons have energy ${\mathrm{E}}_{\min }$ = 1.224 eV. The atomic number of atom is
(a) 2                 (b) 5
(c) 4                 (d) None of these

As the electron in Bohr orbit of Hydrogen atom passes from state n = 2 to n = 1 , the kinetic energy K and potential energy U change as 

(1) K two-fold, U four-fold

(2) K four-fold, U two-fold

(3) K four-fold, U also four-fold

(4) K two-fold, U also two-fold

The ground state energy of hydrogen atom is – 13.6 eV. What is the potential energy of the electron in this state

1. 0 eV                       

2. – 27.2 eV

3. 1 eV                       

4. 2 eV

If the energy of a hydrogen atom in nth orbit is ${\mathrm{E}}_{\mathrm{n}}$, then energy in the nth orbit of a singly ionized helium atom will be 

(1) 4${\mathrm{E}}_{\mathrm{n}}$             

(2) ${\mathrm{E}}_{\mathrm{n}}$/4

(3) 2${\mathrm{E}}_{\mathrm{n}}$             

(4) ${\mathrm{E}}_{\mathrm{n}}$/2

An electron changes its position from orbit n = 4 to the orbit n = 2 of an atom. The wavelength of the emitted radiation’s is (R = Rydberg’s constant)

(1) $\frac{16}{\mathrm{R}}$             

(2) $\frac{16}{3\mathrm{R}}$

(3) $\frac{16}{5\mathrm{R}}$             

(4) $\frac{16}{7\mathrm{R}}$

Which one of the relation is correct between time period and number of orbits while an electron is revolving in a orbit

(1) ${\mathrm{n}}^2$             

(2) $\frac{1}{{\mathrm{n}}^2}$

(3) ${\mathrm{n}}^3$             

(4) $\frac{1}{\mathrm{n}}$

The energy of the highest energy photon of Balmer series of hydrogen spectrum is close to
(1) 13.6 eV             

(2) 3.4 eV

(3) 1.5 eV               

(4) 0.85 eV

In Bohr’s model of hydrogen atom, which of the following pairs of quantities are quantized 

(1) Energy and linear momentum

(2) Linear and angular momentum

(3) Energy and angular momentum

(4) None of the above