The maximum number of neutrons are present in the nuclei of

$1.$ ${\mathrm{O}}_8^{16}$
$2.$ ${\mathrm{Mg}}_{12}^{24}$
$3.$ ${\mathrm{Fe}}_{26}^{56}$
$4.$ ${\mathrm{Sr}}_{38}^{88}$

The complete symbol for the atom with the given atomic number (Z) and atomic mass (A) would be, respectively,

1.  ${}_4{}^9\mathrm{Be}$   ${}_{92}{}^{233}\mathrm{U}$     ${}_4{}^9\mathrm{Be}$

2.  ${}_{17}{}^{35}\mathrm{Cl}$    ${}_{92}{}^{233}\mathrm{U}$    ${}_4{}^9\mathrm{Be}$

3.  ${}_4{}^9\mathrm{Be}$    ${}_{17}{}^{35}\mathrm{Cl}$     ${}_{92}{}^{233}\mathrm{U}$

4. ${}_{92}{}^{233}\mathrm{U}$    ${}_4{}^9\mathrm{Be}$    ${}_{17}{}^{35}\mathrm{Cl}$

Yellow light emitted from a sodium lamp has a wavelength (λ) of 580 nm.

The frequency (ν) and wave number of this yellow light would be, respectively:

1. 517 x 10¹⁴ s^-1 , 172 x 10⁶ m^-1

2. 6.17 x 10¹⁴ s^-1 , 1.72 x 10⁶ m^-1

3. 4.17 x 10¹⁴ s^-1 , 2.72 x 10⁶ m^-1

4. 5.17 x 10¹⁴ s^-1 , 1.72 x 10⁶ m^-1

The energy of the photon with a frequency of 3×10¹⁵ Hz is :

1. 1.988 × ${10}^{-18}$ J
2. 1.588 × ${10}^{-18}$ J
3. 1.288 × ${10}^{-18}$ J
4. 2.988 × ${10}^{-18}$ J

A photon of wavelength 4 × 10^–7 m strikes a metal surface, the work function of the metal being 2.13 eV.  The kinetic energy of emission would be:
 
1.  0.97 eV
2.  97 eV 
3. 4.97 × ${10}^{-19}$ eV
4.  5.84 × 10⁵ eV

The wavelength of the light emitted when the electron returns to the ground state in the H atom, from n = 5 to n = 1, would be: (The ground-state electron energy is –2.18 × 10^-18 j) 
1. Wavelength = 9.498 x 10^-8 km
2. Wavelength = 12.498 x 10^-8 m
3. Wavelength = 9.498 x 10^-8 m
4. Wavelength = 9.498 x 10^-8 cm

The possible values of n, l, and m for the electron present in 3d would be respectively:

1. n = 3, l = 1, m = – 2, – 1, 3, 1, 2

2. n = 3, l = 3, m = – 2, – 1, 0, 1, 2

3. n = 3, l = 2, m = – 2, – 1, 0, 1, 2

4. n = 5, l = 2, m = – 2, – 1, 0, 1, 2

The number of electrons in the species ${\mathrm{H}}_2^{+}$ $,$ ${\mathrm{H}}_2$ $,$ ${\mathrm{O}}_2^{+}$,  are respectively:

1. 15, 2, 1

2. 15, 1, 2

3. 1, 2, 15

4. 2, 1, 15

Orbital that does not exist:

The set of quantum numbers which represent 3p is
1. n =1, l =0;
2, n = 3; l=1
3. n = 4; l =2;
4. n = 4; l = 3