Advertisements
Advertisements
प्रश्न
State and explain Pauli’s exclusion principle.
Advertisements
उत्तर
Pauli’s exclusion principle:
- Statement: “No two electrons in an atom can have the same set of four quantum numbers”. OR “Only two electrons can occupy the same orbital and they must have opposite spins.”
- The capacity of an orbital to accommodate electrons is decided by Pauli’s exclusion principle.
- According to this principle, for an electron belonging to the same orbital, the spin quantum number must be different since the other three quantum numbers are the same.
- The spin quantum number can have two values: `+1/2` and `-1/2`.
- For example, consider helium (He) atom with electronic configuration 1s2.
For the two electrons in 1s orbital, the four quantum numbers are as follows:
Thus, in an atom, any two electrons can have the same three quantum numbers, but the fourth quantum number must be different.Electron number Quantum number Set of values of quantum numbers n l m s 1st Electron 1 0 0 `+1/2` `(1,0,0,+1/2)` 2nd Electron 1 0 0 `-1/2` `(1,0,0,-1/2)` - This leads to the conclusion that an orbital can accommodate a maximum of two electrons and if it has two electrons, they must have opposite spin.
APPEARS IN
संबंधित प्रश्न
Using s, p, d notations, describe the orbital with the following quantum numbers n = 4; l = 2.
Choose the correct option.
p-orbitals are _________ in shape.
Define the term Electronic configuration.
Explain the anomalous behaviour of copper.
Write condensed orbital notation of electronic configuration of the following element:
Oxygen (Z = 8)
Write condensed orbital notation of electronic configuration of the following element:
Chlorine (Z = 17)
Draw shapes of 2s orbitals.
Draw shapes of 2p orbitals.
The electronic configuration of oxygen is written as 1s2 2s2 \[\ce{2p^2_{{x}}}\] \[\ce{2p^1_{{y}}}\] \[\ce{2p^1_{{z}}}\] and not as 1s2 2s2 \[\ce{2p^2_{{x}}}\], \[\ce{2p^2_{{y}}}\] \[\ce{2p^0_{{z}}}\], Explain.
The principal quantum number (n) and magnetic quantum number (ml) for the valence electrons of rubidium atom (Z = 37) are ____________ respectively.
The designation of a subshell with n = 6 and l = 2 is ____________.
Which one of the following orders is CORRECT in case of energy of the given subshells?
P: n = 4; l = 3
Q: n = 5; I = 1
R: n = 5; l = 0
S: n = 4; l = 2
Which one of the following is NOT possible?
Which of the following properties of atom could be explained correctly by Thomson Model of atom?
The number of radial nodes for 3p orbital is ______.
Total number of orbitals associated with third shell will be ______.
Orbital angular momentum depends on ______.
Which of the following sets of quantum numbers are correct?
| `n` | `l` | `m_l` | |
| (i) | 1 | 1 | +2 |
| (ii) | 2 | 1 | +1 |
| (iii) | 3 | 2 | –2 |
| (iv) | 3 | 4 | –2 |
Nickel atom can lose two electrons to form \[\ce{Ni^{2+}}\] ion. The atomic number of nickel is 28. From which orbital will nickel lose two electrons.
The arrangement of orbitals on the basis of energy is based upon their (n + l) value. Lower the value of (n + l), lower is the energy. For orbitals having same values of (n + l), the orbital with lower value of n will have lower energy.
Based upon the above information, arrange the following orbitals in the increasing order of energy.
1s, 2s, 3s, 2p
The arrangement of orbitals on the basis of energy is based upon their (n + l) value. Lower the value of (n + l), lower is the energy. For orbitals having same values of (n + l), the orbital with lower value of n will have lower energy.
Based upon the above information, arrange the following orbitals in the increasing order of energy.
5p, 4d, 5d, 4f, 6s
The arrangement of orbitals on the basis of energy is based upon their (n + l) value. Lower the value of (n + l), lower is the energy. For orbitals having same values of (n + l), the orbital with lower value of n will have lower energy.
Based upon the above information, arrange the following orbitals in the increasing order of energy.
5f, 6d, 7s, 7p
What is the difference between the terms orbit and orbital?
Match the following
| (i) Photon | (a) Value is 4 for N shell |
| (ii) Electron | (b) Probability density |
| (iii) ψ2 | (c) Always positive value |
| (iv) Principal quantum number n | (d) Exhibits both momentum and wavelength |
Match species given in Column I with the electronic configuration given in Column II.
| Column I | Column II |
| (i) \[\ce{Cr}\] | (a) [Ar]3d84s0 |
| (ii) \[\ce{Fe^{2+}}\] | (b) [Ar]3d104s1 |
| (iii) \[\ce{Ni^{2+}}\] | (c) [Ar]3d64s0 |
| (iv) \[\ce{Cu}\] | (d) [Ar] 3d54s1 |
| (e) [Ar]3d64s2 |
In assigning R - S configuration, which among the following groups has highest priority?
What are the possible values of magnetic quantum number for p orbital?
