An electron in the n = 1 orbit of hydrogen atom is bound by 13.6 eV. If a hydrogen atom is in the n = 3 state, how much energy is required to ionize it 
(1) 13.6 eV                     

(2) 4.53 eV

(3) 3.4 eV                       

(4) 1.51 eV

Which of the following statements about the Bohr model of the hydrogen atom is false 

(1) Acceleration of electron in n = 2 orbit is less than that in n = 1 orbit

(2) Angular momentum of electron in n = 2 orbit is more than that in n = 1 orbit

(3) Kinetic energy of electron in n = 2 orbit is less than that in n = 1 orbit

(4) Potential energy of electron in n = 2 orbit is less than that in n = 1 orbit

The ratio of the frequencies of the long wavelength limits of Lyman and Balmer series of hydrogen spectrum is

(1) 27 : 5                   

(2) 5 : 27

(3) 4 : 1                     

(4) 1 : 4

Which of the following transitions in a hydrogen atom emits photon of the highest frequency

(1) n = 1 to n = 2               

(2) n = 2 to n = 1

(3) n = 2 to n = 6               

(4) n = 6 to n = 2

Which of the transitions in hydrogen atom emits a photon of lowest frequency (n = quantum number)
(1) n = 2 to n = 1             

(2) n = 4 to n = 3

(3) n = 3 to n = 1             

(4) n = 4 to n = 2

According to Bohr's theory, the expressions for the kinetic and potential energy of an electron revolving in an orbit is given respectively by
(a)$+\frac{{\mathrm{e}}^2}{8{\mathrm{\pi \epsilon }}_0\mathrm{r}}$ and  $-\frac{{\mathrm{e}}^2}{4{\mathrm{\pi \epsilon }}_0\mathrm{r}}$            (b) $+\frac{8{\mathrm{\pi \epsilon }}_0{\mathrm{e}}^2}{\mathrm{r}}$ and $-\frac{4{\mathrm{\pi \epsilon }}_0{\mathrm{e}}^2}{\mathrm{r}}$
(c) $-\frac{{\mathrm{e}}^2}{8{\mathrm{\pi \epsilon }}_0\mathrm{r}}$ and $-\frac{{\mathrm{e}}^2}{4{\mathrm{\pi \epsilon }}_0\mathrm{r}}$            (d) $+\frac{{\mathrm{e}}^2}{8{\mathrm{\pi \epsilon }}_0\mathrm{r}}$ and $+\frac{{\mathrm{e}}^2}{4{\mathrm{\pi \epsilon }}_0\mathrm{r}}$

The absorption transitions between the first and the fourth energy states of hydrogen atom are 3. The emission transitions between these states will be 
1. 3             

2. 4

3. 5             

4. 6

The ratio of longest wavelength and the shortest wavelength observed in the five spectral series of emission spectrum of hydrogen is 
(1) $\frac{4}{3}$             

(2) $\frac{525}{376}$

(3) 25

(4) $\frac{900}{11}$

In Bohr's model of hydrogen atom, let PE represents potential energy and TE the total energy. In going to a higher level 

(1) PE decreases, TE increases

(2) PE increases, TE increases

(3) PE decreases, TE decreases

(4) PE increases, TE decreases

 According to Bohr's model, the radius of the second orbit of helium atom is 
(1) 0.53 Å             

(2) 1.06 Å

(3) 2.12 Å             

(4) 0.265 Å