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प्रश्न
Write a note on ‘Principal Quantum number.
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उत्तर
Principal quantum number (n):
- Principal quantum number indicates the principal shell or main energy level to which the electron belongs.
- It is denoted by ‘n’ and is a positive integer with values 1, 2, 3, 4, 5, 6, ….
- A set of atomic orbitals with a given value of ‘n’ constitutes a single shell. These shells are also represented by the letters K, L, M, N, etc.
- With an increase of ‘n’, the number of allowed orbitals in that shell increases and is given by n2.
- The allowed orbitals in the first four shells are given below:
Principal quantum number (n) Shell symbol Allowed number of orbitals (n2) Size of shell 1 K 1 ↓ increases 2 L 4 3 M 9 4 N 16 - As the value of ‘n’ increases, the distance of the shell from the nucleus increases, and the size of the shell increases. Its energy also goes on increasing.
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संबंधित प्रश्न
Using s, p, d notations, describe the orbital with the following quantum numbers n = 1, l = 0.
Using s, p, d notations, describe the orbital with the following quantum numbers n = 3; l =1.
Choose the correct option.
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Explain the anomalous behaviour of copper.
Explain the anomalous behaviour of chromium.
Write orbital notations for the electron in orbitals with the following quantum numbers.
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If n = 3, what are the quantum number l and m?
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.
Using the concept of quantum numbers, calculate the maximum numbers of electrons present in the ‘M’ shell. Give their distribution in shells, subshells, and orbitals.
How many electrons can fit in the orbital for which n = 4 and l = 2?
Which of the following options does not represent ground state electronic configuration of an atom?
Which of the following properties of atom could be explained correctly by Thomson Model of atom?
Total number of orbitals associated with third shell will be ______.
Orbital angular momentum depends on ______.
The pair of ions having same electronic configuration is ______.
In which of the following pairs, the ions are iso-electronic?
(i) \[\ce{Na^{+}, Mg^{2+}}\]
(ii) \[\ce{Al3^{+}, O-}\]
(iii) \[\ce{Na+ , O2-}\]
(iv) \[\ce{N3-, Cl-}\]
Calculate the total number of angular nodes and radial nodes present in 3p orbital.
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Based upon the above information, arrange the following orbitals in the increasing order of energy.
1s, 2s, 3s, 2p
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Based upon the above information, arrange the following orbitals in the increasing order of energy.
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Based upon the above information, solve the questions given below:
Which of the following orbitals has the lowest energy?
5p, 5d, 5f, 6s, 6p
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 |
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 orbitals?
Which of the following element do not follow Aufbau principle?
