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

Every series of hydrogen spectrum has an upper and lower limit in wavelength. The spectral series which has an upper limit of wavelength equal to 18752 Å is 
1. Balmer series               

2. Lyman series

3. Paschen series               

4. Pfund series

(Rydberg constant R = $1.097\times {10}^7$ per metre)

An electron jumps from the 4th orbit to the 2nd orbit of hydrogen atom. Given the Rydberg's constant R = ${10}^5 {\mathrm{cm}}^{-1}$. The frequency in Hz of the emitted radiation will be 
(a) $\frac{3}{16}\times {10}^5$           (b) $\frac{3}{16}\times {10}^{15}$
(c) $\frac{9}{16}\times {10}^{15}$          (d) $\frac{3}{4}\times {10}^{15}$

The ionisation potential of hydrogen atom is 13.6 volt. The energy required to remove an electron in the n = 2 state of the hydrogen atom is 

A beam of fast-moving alpha particles were directed towards a thin film of gold. The parts \(A', B',\) and \(C'\) of the transmitted and reflected beams corresponding to the incident parts \(A,B\) and \(C\) of the beam, are shown in the adjoining diagram. The number of alpha particles in: