The number of protons, neutrons, and electrons in  \( _{71}^{175}Lu\) respectively, are:

1.  104, 71 and 71

2.  71, 71 and 104

3.  175, 104 and 71

4.  71, 104 and 71

The energy of an electron in the first Bohr's orbit of an H-atom is -13.6 eV. The possible energy value (s) of the excited state(s) for electrons in Bohr's orbits of hydrogen is (are):

1. -3.4 eV

2. -4.2 eV

3. -6.8 eV

4. +6.8 eV

An ion among the following that has the same radius as a hydrogen atom, having n=1, is 

1. ${\mathrm{He}}^{+},$ $n=2$

2. ${\mathrm{Li}}^{2+},n=2$

3. ${\mathrm{Be}}^{3+},$ $n=2$

4. ${\mathrm{Li}}^{2+},\mathrm{n}=3$

The number of electrons with the azimuthal quantum number l = 1 and 2 for Cr ₂₄ in ground state is

1. 16 and 5

2. 12 and 5

3. 16 and 4

4. 12 and 4

The wavelength of the radiation emitted when in a H atom, the electron falls from infinity to stationary state (n=1), is:

1. $15$ $nm$

2. 192 nm

3. 406 nm

4. 91 nm

The concept that contradicts the Bohr Model of an atom is: 

Electrons are emitted with zero velocity from a metal surface when it is exposed to radiation of
wavelength 6800 Å. The work function (W₀ ) of the metal is: 

1. 3.109 x 10^-20 J

2. 2.922 x 10^-19 J

3. 4.031 x 10¹⁹ J

4. 2.319 x 10^-18 J

The maximum number of emission lines obtained when the excited electron of the H atom jumps from n = 6 to the ground state is -

1. 30

2. 21

3. 15

4. 28

The ionization energy for H atom in the ground state is \(2.18 \times10^{-18}~ \mathrm J.\) The process energy requirements will be: \(( He^+(g) \rightarrow He^{2+}(g) + e^- )\)

The ejection of the photoelectron from the silver metal can be stopped by applying a voltage of 0.35 eV when the radiation having a wavelength of 256.7 nm is used. The work function for silver metal is: 

1. 3.40 eV

2. 5.18 eV

3. 4.48 eV

4. -4.40 eV