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In the uncertainty in velocity and position of a minute particle in space are, \( 2.4 \times 10^{-26} \; \mathrm{(m\,s^{-1})} \) and \( 10^{-4} \; \mathrm{(m)} \) respectively. The mass of the particle in g is __________ (Nearest integer)
(Given : \( h = 6.626 \times 10^{-34} \; \mathrm{J\,s} \) )

The pair, in which ions are isoelectronic with \( \mathrm{Al^{3+}} \) is:

Consider an imaginary ion \( ^{48}_{22}X^{3-} \). The nucleus contains '\( a \)'% more neutrons than the number of electrons in the ion. The value of 'a' is ______ (nearest integer)

Which of the following is the correct plot for the probability density \( \psi^2(r) \) as a functions of distance \( r \) of the electron from the nucleus for \( 2s \) orbitals?

The minimum uncertainty in the speed of an electron in an one dimensional region of length \( 2a_{0} \) (Where \( a_{0} = \) Bohr radius \( 52.9\,\mathrm{pm} \)) is _________ \( \mathrm{km\,s^{-1}} \).
(Given: Mass of electron \( = 9.1 \times 10^{-31}\,\mathrm{kg} \), Planck’s constant \( h = 6.63 \times 10^{-34}\,\mathrm{J\,s} \))

The correct decreasing order of energy for the orbital having, following set of quantum numbers:
(A) \( n = 3, \, l = 0, \, m = 0 \)
(B) \( n = 4, \, l = 0, \, m = 0 \)
(C) \( n = 3, \, l = 1, \, m = 0 \)
(D) \( n = 3, \, l = 2, \, m = 1 \)
is:

Which of the following sets of quantum numbers is not allowed?

If the work function of a metal is \( 6.63 \times 10^{-19} \, \text{J} \), the maximum wavelength of the photon required to remove a photoelectron from the metal is ______ \( \text{nm} \). (nearest integer) [Given: \( h = 6.63 \times 10^{-34} \, \text{J s} \), and \( c = 3 \times 10^{8} \, \text{m s}^{-1} \)]

The metal ion (in gaseous state) with lowest spin-only magnetic moment value is

The energy of one mole of photons of radiation of wavelength \( 300 \) \( \text{nm} \) is (Given : \( h = 6.63 \times 10^{-34} \) \( \text{J s} \), \( N_{A} = 6.02 \times 10^{23} \) \( \text{mol}^{-1} \), \( c = 3 \times 10^{8} \) \( \text{m s}^{-1} \) )

The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is:
[Given: The threshold frequency of platinum is \( 1.3 \times 10^{15} \, \mathrm{s}^{-1} \) and \( h = 6.6 \times 10^{-34} \, \text{J s} \).]

If the wavelength for an electron emitted from H-atom is \( 3.3 \times 10^{-10} \, \text{m} \), then energy absorbed by the electron in its ground state compared to minimum energy required for its escape from the atom, is ________ times. (Nearest integer)
[Given: \( h = 6.626 \times 10^{-34} \, \text{J s} \)]
Mass of electron \( = 9.1 \times 10^{-31} \, \text{kg} \)

The longest wavelength of light that can be used for the ionisation of lithium atom (Li) in its ground state is \( x \times 10^{-8} \, \text{m} \). The value of \( x \) is __________. (Nearest Integer)
(Given : Energy of the electron in the first shell of the hydrogen atom is \( -2.2 \times 10^{-18} \, \text{J} \) ; \( h = 6.63 \times 10^{-34} \, \text{J s} \) and \( c = 3 \times 10^{8} \, \text{m s}^{-1} \))

If the radius of the \( 3^{\text{rd}} \) Bohr’s orbit of hydrogen atom is \( r_3 \) and the radius of \( 4^{\text{th}} \) Bohr’s orbit is \( r_4 \). Then:

Consider the following set of quantum numbers.

The number of correct sets of quantum numbers is ________.

Given below are two statements. One is labeled as Assertion A and the other is labeled as Reason R.
Assertion A: Energy of \( 2s \) orbital of hydrogen atom is greater than that of \( 2s \) orbital of lithium.
Reason R: Energies of the orbitals in the same subshell decrease with increase in the atomic number.
In the light of the above statements, choose the correct answer from the options given below:

Which of the following statements are correct?
(a) The electronic configuration of Cr is \( \mathrm{[Ar]\, 3d^5\, 4s^1} \)
(b) The magnetic quantum number may have a negative value
(c) In the ground state of an atom, the orbitals are filled in order of their increasing energies
(d) The total number of nodes are given by \( n - 2 \)
Choose the most appropriate answer from the options given below:

When the excited electron of a H-atom from \( n = 5 \) drops to the ground state, the maximum number of emission lines observed are ________.

The wavelength of an electron and a neutron will become equal when the velocity of the electron is \( x \) times the velocity of neutron. The value of \( x \) is __________. (Nearest Integer)
(Mass of electron is \( 9.1 \times 10^{-31} \, \text{kg} \) and mass of neutron is \( 1.6 \times 10^{-27} \, \text{kg} \))

Identify the incorrect statement form the following.

The spin only magnetic moment of the complex present in Fehling’s reagent is ______ B.M. (Nearest integer).

Given below are the quantum numbers for \( 4 \) electrons.
(a) \( n = 3, \, l = 2, \, m_1 = 1, \, m_s = +{1}/{2} \)
(b) \( n = 4, \, l = 1, \, m_1 = 0, \, m_s = +{1}/{2} \)
(c) \( n = 4, \, l = 2, \, m_1 = -2, \, m_s = -{1}/{2} \)
(d) \( n = 3, \, l = 1, \, m_1 = -1, \, m_s = +{1}/{2} \)
The correct order of increasing energy is

Consider the following statements:
(a) The principal quantum number ' \( n \) ' is a positive integer with values of ' \( n \) ' \( = 1, 2, 3, \ldots \).
(b) The azimuthal quantum number ' \( l \) ' for a given ' \( n \) ' (principal quantum number) can have values as ' \( l \) ' \( = 0, 1, 2, \ldots \, n \).
(c) Magnetic orbital quantum number ' \( m_l \) ' for a particular ' \( l \) ' (azimuthal quantum number) has \( (2l + 1) \) values
.(d) \( \pm 1/2 \) 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?

Consider the following pairs of electrons
(A) (a) \( n = 3, \ l = 1, \ m_{l} = 1, \ m_{s} = +\frac{1}{2} \) (b) \( n = 3, \ l = 2, \ m_{l} = 1, \ m_{s} = +\frac{1}{2} \)
(B) (a) \( n = 3, \ l = 1, \ m_{l} = -2, \ m_{s} = -\frac{1}{2} \) (b) \( n = 3, \ l = 2, \ m_{l} = -1, \ m_{s} = -\frac{1}{2} \)
(C) (a) \( n = 4, \ l = 2, \ m_{l} = 2, \ m_{s} = +\frac{1}{2} \) (b) \( n = 3, \ l = 2, \ m_{l} = 2, \ m_{s} = +\frac{1}{2} \)

The pairs of electrons present in degenerate orbitals is/are:

The number of radial and angular nodes in \( 4d \) orbital are, respectively:

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JEE Main 2022 25th June Evening Shift

The metal ion (in gaseous state) with lowest spin-only magnetic moment value is