If in nature there may not be an element for which the principal quantum number n > 4, then the total possible number of elements will be

(1) 60                   

(2) 32

(3) 4                     

(4) 64

In the \(n^{th}\) orbit, the energy of an electron is \(E_{n}=-\frac{13.6}{n^2} ~\text{eV}\) for the hydrogen atom. What will be the energy required to take the electron from the first orbit to the second orbit?
1. \(10.2~\text{eV}\)
2. \(12.1~\text{eV}\)
3. \(13.6~\text{eV}\)
4. \(3.4~\text{eV}\)

The Lyman series of hydrogen spectrum lies in the region

(1) Infrared               

(2) Visible

(3) Ultraviolet             

(4) X- rays

Which one of the series of hydrogen spectrum is in the visible region 

1. Lyman series             

2. Balmer series

3. Paschen series           

4. Bracket series

The Rutherford $\mathrm{\alpha }$-particle experiment shows that most of the $\mathrm{\alpha }$-particles pass through almost unscattered while some are scattered through large angles. What information does it give about the structure of the atom 

(1) Atom is hollow

(2) The whole mass of the atom is concentrated in a small centre called nucleus

(3) Nucleus is positively charged

(4) All the above

Which of the following is true 

(1) Lyman series is a continuous spectrum

(2) Paschen series is a line spectrum in the infrared

(3) Balmer series is a line spectrum in the ultraviolet

(4) The spectral series formula can be derived from the Rutherford model of the hydrogen atom

The energy required to knock out the electron in the third orbit of a hydrogen atom is equal to
(1) 13.6 eV           

(2) $+\frac{13.6}{9}\mathrm{eV}$

(3) $-\frac{13.6}{3}\mathrm{eV}$      

(4) $-\frac{3}{13.6}\mathrm{eV}$

An electron has a mass of $9.1\times {10}^{-31} \mathrm{kg}$. It revolves round the nucleus in a circular orbit of radius $0.529\times {10}^{-10}$ metre at a speed of $2.2\times {10}^6 \mathrm{m}/\mathrm{s}$. The magnitude of its linear momentum in this motion is

(a) $1.1\times {10}^{-34 }$kg-m/s             (b) $2.0\times {10}^{-24}$ kg-m/s 
(c) $4.0\times {10}^{-24}$ kg-m/s           (d) $4.0\times {10}^{-31}$ kg-m/s

The ionization potential for second He electron is
(1) 13.6 eV                 

(2) 27.2 eV

(3) 54.4 eV                 

(4) 100 eV

The energy required to remove an electron in a hydrogen atom from n = 10 state is 
(1) 13.6 eV                   

(2) 1.36 eV

(3) 0.136 eV                 

(4) 0.0136 eV