List of top Chemistry Questions on Structure of atom asked in JEE Main

Consider the following statements :
(A) The principal quantum number ‘n’ is a positive integer with values of ‘n’ = 1, 2, 3, ….
(B) The azimuthal quantum number ‘l’ for a given ‘n’ (principal quantum number) can have values as ‘l’ = 0, 1, 2, …n
(C) Magnetic orbital quantum number ‘m_l’ for a particular ‘l’ (azimuthal quantum number) has (2l + 1) values.
(D) ±1/2 are the two possible orientations of electron spin.
(E) For l = 5, there will be a total of 9 orbital
Which of the above statements are correct?

The minimum uncertainty in the speed of an electron in an one dimensional region of length 2a₀ (Where a₀ = Bohr radius 52.9 pm) is _____ km s^–1.
(Given : Mass of electron = 9.1 × 10^–31 kg, Planck’s constant h = 6.63 × 10^–34Js)

The number of radial and angular nodes in 4d orbital are, respectively

Which of the following is the correct plot for the probability density ψ²(r) as a function of distance ‘r’ of the electron from the nucleus for 2s orbital?

The de Broglie wavelength of an electron in the $4^{th}$ Bohr orbit is :

For emission line of atomic hydrogen from $n_i = 8$ to $n_f $ = the plot of wave number $(\bar{v})$ against $( \frac{1}{n^2})$ will be (The Ry dberg constant, $R_H$ is in wave number unit).

Heat treatment of muscular pain involves radiation of wavelength of about $900\, nm$. Which spectral line of H-atom is suitable for this purpose ? $[R_H = 1 \times 10^5 \; cm^{-1}, h = 6.6 \times 10^{-34} \; Js, c = 3 \times 10^8 \; ms^{-1}]$

The size of the iso-electronic species $Cl^-, Ar$ and $ {Ca^{2+}}$ is affected by -

Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying $0.5\, V$ when the radiation of $250\, nm$ is used. The work function of the metal is :

Which of the following statements is false?

If the shortest wavelength in Lyman series of hydrogen atom is $A$, then the longest wavelength in Paschen series of $He^{+}$ is :

The electron in the hydrogen atom undergoes transition from higher orbitals to orbital of radius $211.6\, pm$. This transition is associated with

A stream of electrons from a heated filament was passed between two charged plates kept at a potential difference $V$ esu. If $e$ and $m$ are charge and mass of an electron, respectively, then the value of $h/ \lambda$ (where $\lambda$ is wavelength associated with electron wave) is given by :

The total number of orbitals associated with the principal quantum number 5 is :

At temperature T, the average kinetic energy of any particle is $\frac{3}{2}$ kT. The de Broglie wavelength follows the order :

Which of the following is the energy of a possible excited state of hydrogen?

If $\lambda_{0}$ and $\lambda$ be the threshold wavelength and wavelength of incident light, the velocity of photoelectron ejected from the metal surface is :

The energy of an electron in first Bohr orbit of $H$ - atom is $- 13.6\, eV$. The energy value of electron in the excited state of $Li^{2+}$ is :

Based on the equation : $\Delta E = -2.0 \times 10^{-18} J \left(\frac{1}{n^{2}_{2}}-\frac{1}{n^{2}_{1}}\right)$ the wavelength of the light that must be absorbed to excite hydrogen electron from level n=l to level n=2 will be : $\left(h = 6.625 \times 10^{-34} \,Js, C= 3\times10^{8} \,ms^{-1}\right)$

If $m$ and $e$ are the mass and charge of the revolving electron in the orbit of radius $r$ for hydrogen atom, the total energy of the revolving electron will be :

Excited hydrogen atom emits light in the ultraviolet region at $2.47 \times 10^{15}\, Hz$. With this frequency, the energy of a single photon is : $(h = 6.63 \times 10^{-34}\, Js)$

Given (A) $n=5, m_{\ell} =+1$ (B) $n=2, \ell=1, m_{\ell} =1, m_{s} =-\frac{1}{2}$ The maximum number of electron(s) in an atom that can have the quantum numbers as given in (A) and (B) are respectively:

If the ionisation potential of the hydrogen atom is