English

Write a note on ‘Principal Quantum number.

Advertisements
Advertisements

Question

Write a note on ‘Principal Quantum number.

Answer in Brief
Advertisements

Solution

Principal quantum number (n):

  1. Principal quantum number indicates the principal shell or main energy level to which the electron belongs.
  2. It is denoted by ‘n’ and is a positive integer with values 1, 2, 3, 4, 5, 6, ….
  3. 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.
  4. With an increase of ‘n’, the number of allowed orbitals in that shell increases and is given by n2.
  5. 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
  6. 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.
shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Structure of Atom - Exercises [Page 54]

APPEARS IN

Balbharati Chemistry [English] Standard 11 Maharashtra State Board
Chapter 4 Structure of Atom
Exercises | Q 6. (Q) | Page 54

RELATED QUESTIONS

Using s, p, d notations, describe the orbital with the following quantum numbers n = 3; l =1.


Using s, p, d notations, describe the orbital with the following quantum numbers n = 4; l = 2.


Using s, p, d notations, describe the orbital with the following quantum numbers n = 4; l =3.


Choose the correct option.

“No two electrons in the same atoms can have identical set of four quantum numbers”. This statement is known as -


State Heisenberg uncertainty principle.


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 orbital notations for the electron in orbitals with the following quantum numbers.

n = 3, l = 2


Write condensed orbital notation of electronic configuration of the following element:

Carbon (Z = 6)


Write condensed orbital notation of electronic configuration of the following element:

Calcium (Z = 20)


Draw shapes of 2s 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.


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.


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 is NOT possible?


Which of the following options does not represent ground state electronic configuration of an atom?


Number of angular nodes for 4d orbital is ______.


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) \[\ce{N3-, Cl-}\]


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 assigning R - S configuration, which among the following groups has highest priority?


Which one of the following laws will represent the pairing of electrons in a subshell after each orbital is filled with one electron?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×