Advertisements
Advertisements
प्रश्न
Write a note on ‘Principal Quantum number.
Advertisements
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.
APPEARS IN
संबंधित प्रश्न
Choose the correct option.
p-orbitals are _________ in shape.
Give the names of quantum numbers.
State Hund’s rule of maximum multiplicity with a suitable example.
State the order of filling atomic orbitals following Aufbau principle.
Write condensed orbital notation of electronic configuration of the following element:
Chlorine (Z = 17)
Indicate the number of unpaired electron in:
Cr (Z = 24)
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
The three electrons have the following set of quantum numbers:
X = 6, 1, −1, `+1/2`
Y = 6, 0, 0, `+1/2`
Z = 5, 1, 0, `+1/2`
Identify the CORRECT statement.
How many electrons can fit in the orbital for which n = 4 and l = 2?
Which of the following properties of atom could be explained correctly by Thomson Model of atom?
Number of angular nodes for 4d orbital is ______.
The pair of ions having same electronic configuration is ______.
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 |
Which of the following statements concerning the quantum numbers are correct?
(i) Angular quantum number determines the three dimensional shape of the orbital.
(ii) The principal quantum number determines the orientation and energy of the orbital.
(iii) Magnetic quantum number determines the size of the orbital.
(iv) Spin quantum number of an electron determines the orientation of the spin of electron relative to the chosen axis.
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.
4s, 3s, 3p, 4d
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
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?
4d, 4f, 5s, 5p
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
What is the difference between the terms orbit and orbital?
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 |
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 one of the following laws will represent the pairing of electrons in a subshell after each orbital is filled with one electron?
