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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 = 4; l =3.
State and explain Pauli’s exclusion principle.
Write orbital notations for the electron in orbitals with the following quantum numbers.
n = 2, l = 1
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:
Calcium (Z = 20)
Draw shapes of 2p orbitals.
If n = 3, what are the quantum number l and m?
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.
Indicate the number of unpaired electrons in \[\ce{Si}\] (Z = 14).
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
How many electrons in 19K have n = 3, l = 1?
How many electrons can fit in the orbital for which n = 4 and 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 ______.
Number of angular nodes for 4d orbital is ______.
Total number of orbitals associated with third shell will be ______.
Orbital angular momentum depends on ______.
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) \[\ce{N3-, Cl-}\]
Which of the following orbitals are degenerate?
3dxy, 4dxy 3dz2, 3dyz, 4dyz, 4dz2
Calculate the total number of angular nodes and radial nodes present in 3p orbital.
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
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, solve the questions given below:
Which of the following orbitals has the lowest energy?
5p, 5d, 5f, 6s, 6p
Match the following species with their corresponding ground state electronic configuration.
| Atom / Ion | Electronic configuration |
| (i) \[\ce{Cu}\] | (a) 1s2 2s2 2p6 3s2 3p6 3d10 |
| (ii) \[\ce{Cu^{2+}}\] | (b) 1s2 2s2 2p6 3s2 3p6 3d10 4s2 |
| (iii) \[\ce{Zn^{2+}}\] | (c) 1s2 2s2 2p6 3s2 3p6 3d10 4s1 |
| (iv) \[\ce{Cr^{3+}}\] | (d) 1s2 2s2 2p6 3s2 3p6 3d9 |
| (e) 1s2 2s2 2p6 3s2 3p6 3d3 |
Choose the INCORRECT statement
In the case of R, S configuration the group having the highest priority is ______.
Which one of the following laws will represent the pairing of electrons in a subshell after each orbital is filled with one electron?
