Question 1 :
In a multi-electron atom, which of the following orbitals described by the three quantum members will have the same energy in the absence of magnetic and electric fields?<br>{tex} \begin{array} { l l } { \text { (A) } n = 1 , l = 0 , m = 0 } & { \text { (B) } n = 2 , l = 0 , m = 0 } \\ { \text { (C) } n = 2 , l = 1 , m = 1 } & { \text { (D) } n = 3 , l = 2 , m = 1 } \\ { \text { (E) } n = 3 , l = 2 , m = 0 } \end{array} {/tex}<br>

Question 2 :
Which one of the following constitutes a group of the isoelectronic species?

Question 3 :
Correct order of radius of the <img style='object-fit:contain' src='https://storage.googleapis.com/teachmint/question_assets/JEE%20Main/5e7980dcd3f9ab617fcdb1d0' height='17' width='11' >st orbit of H, He+, Li2+, Be3+ is :

Question 5 :
Which of the following represents the correct set of the four quantum numbers of 4{tex} d {/tex} -electrons?

Question 6 :
The highest excited state that an unexcited hydrogen atom can reach when they are bombarded with 12.2 eV electron is:

Question 8 :
If proton, electron and &alpha; - particle have equal kinetic energy, their de-Broglie wavelengths would be in the order -

Question 9 :
<img style='object-fit:contain' src='https://storage.googleapis.com/teachmint/question_assets/JEE%20Main/5e79806bc6cb6261b35b2732' height='21' width='32' > and <img style='object-fit:contain' src='https://storage.googleapis.com/teachmint/question_assets/JEE%20Main/5e79806badb2ea6185a75f6f' height='23' width='36' > are -

Question 10 :
The uncertainty in the momentum of an electron is 1.0 &times; 10-5 kg m s-1 . The uncertainty in its position will be:

Question 13 :
Which of the following represent(s) the correct set of four quantum numbers of a {tex} 4 \mathrm { d } {/tex} electron?

Question 15 :
Calculate the wavelength of light required to break the bond between two {tex} \mathrm { Cl } {/tex} atoms in {tex} \mathrm { Cl } _ { 2 } {/tex} molecules ({tex}\mathrm {(BE)_{cl-cl}}{/tex} = 243 kJ mole {tex}^{-1}{/tex}

Question 16 :
In a multi-electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric field ?<br>(i) n = 1, l = 0, m = 0 (ii) n =2, l = 0, m = 0 (iii) n = 2, l = 1, m = 1 (iv) n = 3, l = 2, m =1 (v) n = 3, l = 2, m = 0

Question 17 :
The number of electrons having l = 0 in chlorine atom (Z = 17) is

Question 18 :
If 10^-17 J of light energy is needed by the interior of human eye to see an object. The photons of green light (&lambda; = 550nm) needed to see the object are.

Question 19 :
Which of the following quantum numbers are correct for the outermost electron of sodium atom?

Question 20 :
In a multi-electron atom, which of the following orbitals described by the three quantum members will have the same energy in the absence of magnetic and electric fields?<br>{tex} \begin{array} { l l } { \text { (A) } n = 1 , l = 0 , m = 0 } & { \text { (B) } n = 2 , l = 0 , m = 0 } \\ { \text { (C) } n = 2 , l = 1 , m = 1 } & { \text { (D) } n = 3 , l = 2 , m = 1 } \\ { \text { (E) } n = 3 , l = 2 , m = 0 } \end{array} {/tex}<br>

Question 22 :
____ Series of lines are the only lines in hydrogen spectrum which appear in the visible region.

Question 23 :
Radius of 2nd shell of {tex}\mathrm{He}^{+}{/tex} (where {tex} \mathrm { a } _ { 0 } {/tex} - Bohr radius)

Question 24 :
The element having no neutron in the nucleus of its atom is

Question 25 :
Which one is not in agreement with Bohr's model of atom?