Facebook Twitter Instagram
    ScienceMotive
    • Class 9
      • Matter in Our Surroundings
      • Is Matter Around Us Pure
      • Atoms and Molecules
      • Structure of the Atom
      • The Fundamental Unit of Life
    • Class 10
      • Chemistry
    • Class 11
      • Chemisrty
        • Chapter – 1 Some Basic Concepts of Chemistry
        • Chapter – 2 Structure Of Atom
        • Chapter – 3 Classification of Elements and Periodicity in Properties
        • Chapter – 4 Chemical Bonding and Molecular Structure
        • Chapter – 5 States of Matter
        • Chapter – 6 Thermodynamics
        • Chapter – 7 Equilibrium
        • Chapter – 8 Redox Reaction
        • Chapter – 10 s-Block Elements
        • Chapter – 13 Hydrocarbons
    • Class 12
      • Chemistry
        • The Solid State
        • Solutions
        • Electrochemistry
        • Chemical Kinetics
        • Surface Chemistry
        • p – Block Elements
        • d & f Block Elements
        • Coordination Compounds
        • Haloalkanes and Haloarenes
        • Alcohols, Phenols and Ethers
        • Aldehydes, Ketones and Carboxylic Acids
        • Amines
        • Biomolecules
        • Polymers
        • Chemistry in Everyday Life
    • Practice Questions
      • +1
      • +2
    • Test Series
      • Class 9 Test Series
      • Class 10 Test Series
      • Class 11 Test Series
      • Class 12 Test Series
    • World
      • Current Affairs
      • General Knowledge
    ScienceMotive
    Home » Quantum Mechanics and Quantum Numbers

    Quantum Mechanics and Quantum Numbers

    Dr. Vikas JasrotiaBy Dr. Vikas JasrotiaOctober 28, 2020No Comments
    Share
    Facebook WhatsApp Telegram Twitter Email

    Quantum Mechanics and Quantum Numbers

    Quantum Mechanics and Quantum Numbers post provides complete information about quantum numbers with examples and wave function

    Quantum Mechanics: Quantum mechanics takes into account the dual behavior of matter. An equation, given by Schrodinger, which has a better physical interpretation in terms of wave properties is Ĥ ψ = Eψ. Where Ĥ is called Hamiltonian operator, E is the total energy of the system (K.E + P.E) and ψ is called the wave function.

    Physical Significance of ψ: The wave function (ψ) is a mathematical function and it has no physical significance. Wave functions of hydrogen or hydrogen-like species with one electron are called atomic orbitals. All the information about the electron in an atom is stored in its orbital wave function ψ.Its square ψ2 is proportional to the probability of finding the electron at a given point around the nucleus and is always positive.

    Quantum numbers: There are a set of four quantum numbers that specify the energy, size, shape, and orientation of an orbital. The Quantum number gives the address of the electron.                                                                                                                                                        These are:
    (i) Principal quantum number (n)
    (ii) Azimuthal quantum number (l)
    (iii) Magnetic quantum number (m)
    (iv) Electron spin quantum number (ms)

    Principal Quantum Number: The following formations are obtained from n.
    1. It gives the size of the orbit.
    2. It gives the energy of an electron in an orbit.
    3. It gives the shell in which the electron is found.
    4. It also gives the average distance between the electron and the nucleus. As the value of n increases, the distance between the electron and the nucleus also increases.

    n 1 2 3 4
    Shell no. K L M N
    Total number of orbitals in a shell = n2 1 4 9 16
    Maximum number of electrons = 2n2 2 8 18 32

     

    Azimuthal quantum number (l): Azimuthal quantum number. ‘l’ is also known as orbital angular momentum or subsidiary quantum number. It identified the subshell and the three-dimensional shape of the orbital. It also determines the number of subshells or sub levels in a shell. The total number of subshells in a particular shell is equal to the value of n. l = 0, 1, 2… (n-1)
    For example, when n = 1, the value of Ɩ is only 0.
    For n = 2, the possible value of Ɩ can be 0 and 1.
    For n = 3, the possible Ɩ values are 0,1 and 2.
    Ɩ= 0 represents s orbital, Ɩ = 1 represents p orbital, Ɩ = 2 represents d orbital and Ɩ = 3 represents f orbital. The number of sub-shells in a principal shell is equal to the value of n.
    When n = 1, Ɩ= 0. i.e. K shell contains only one sub-shell – s subshell
    when n = 2, Ɩ = 0 and1. i.e. L shell contains two subshells – s and p subshells
    when n = 3, Ɩ = 0, 1 and 2. i.e. M shell contains three subshells – s, p and d subshells.

     

    Magnetic Quantum Number (m): It gives information about the orientation of orbitals in space. For a given ‘Ɩ’ value, there are 2Ɩ+1 possible values for m and these values are given by: m = – Ɩ to 0 to + lThus for Ɩ = 0, m = 0 {2(0)+1 = 1}. i.e. s sub shell contains only one orbital called s orbital.
    For Ɩ = 1, mƖ = –1, 0 and +1, {2(1)+1 = 3}. i.e. p subshell contains three orbitals called p orbitals (px, py and pz).
    For Ɩ = 2, m = –2, –1, 0, +1 and +2, {2(2)+1 = 5}. i.e. d subshell contains five orbitals called d orbitals (dxy, dyz, dzx, dx2-y2, dz2).

     

    Spin Quantum Number (s or ms): It refers to the orientation of the spin of the electron. It can have two values +1/2 and -1/2. +1/2 identifies the clockwise spin and -1/2 identifies the anti-clockwise spin.

     

    Summary of Quantum Numbers

     

    Concept of Orbit and Orbital

        

    Advertisement
    Share. Facebook Twitter Pinterest LinkedIn Tumblr Email
    Dr. Vikas Jasrotia
    • Website

    Related Posts

    Write the favourable factors for the formation of ionic bond

    October 17, 2022

    Chemical Bonding Class 11 Questions and Answers PDF

    October 16, 2022

    Chemical Bonding and Molecular Structure – Short Notes

    October 14, 2022

    Leave A Reply Cancel Reply

    READ ALSO

    Carbon and Its Compounds

    January 23, 2023

    An element X (atomic number = 17) reacts with an element Y (atomic number = 20) to form a divalent halide.

    January 10, 2023

    General Science Questions and Answers PDF

    October 20, 2022

    When Conc. H2SO4 was added to an unknown salt in a test tube, and a brown gas (A) was evolved. This gas intensified when copper turnings were added to the test tube. On cooling gas (A) changed into a colorless gas (B). Identify the gases ‘A’ and ‘B’. Write the equations for the reactions involved.

    October 19, 2022

    Carbon and Its Compounds

    By Dr. Vikas JasrotiaJanuary 23, 2023

    CARBON AND ITS COMPOUNDS Carbon plays a very important role for all living beings. The…

    Class 10

    An element X (atomic number = 17) reacts with an element Y (atomic number = 20) to form a divalent halide.

    By Dr. Vikas JasrotiaJanuary 10, 2023

    Que. An element X (atomic number = 17) reacts with an element Y (atomic number…

    General Knowledge

    General Science Questions and Answers PDF

    By Dr. Vikas JasrotiaOctober 20, 2022

    General Science Questions and Answers PDF General Science Questions and Answers PDF Que 1. Which…

    Advertisement
    Advertisement
    Facebook Twitter Instagram Pinterest YouTube
    • Disclaimer
    • Contact Us
    • Privacy Policy 
    • Terms and Conditions
    © 2023 All Rights Reserved ScienceMotive.

    Type above and press Enter to search. Press Esc to cancel.