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Magnetic Quantum Number MASTER CLASS TEACHER TEACHER Post-class: doubt solving More than 2 Million doubts solved Assessment: regular tests Enroll into Multiple course How to Avail Discount ? Special Discount for this class Apply Coupon Code: MRPRO Visit: https://vdnt.in/YTPRO Link in Description Wave Particle Quantum numbers First three derived from Schordinger’s wave equation. Quantum numbers are like the postal address of a man. To know about a particular person we should know about his country , his town, his lane and his house number. Quantum numbers Quantum numbers is defined as the set of four numbers with the help of which we can get the complete information about all the electrons in an atoms. i.e. Location , energy , the type of orbital occupied , shape and orientation of the orbital etc. Types of quantum numbers Principal quantum numbers(n) ● It represent the distance of the electron from the nucleus and also called as Shell of electron. It determines the size of the electron cloud. n = 1 K 2 L 3 M 4 N Principal quantum numbers ❏ The maximum number of electrons present in any principal shell is given by 2n2 where n is the number of the principal shell. 2. Azimuthal/ Angular momentum quantum number (l) Azimuthal quantum numbers tells about: ❏ The number of subshells present in the main shell. 2. Azimuthal/ Angular momentum quantum number (l) ❏ The angular momentum of the electron present in any subshell. 2. Azimuthal/ Angular momentum quantum number (l) ❏ The relative energies of the various subshells. 2. Azimuthal/ Angular momentum quantum number (l) ❏ The shape of the various subshell present within the same principal shell. 2. Azimuthal/ Angular momentum quantum number (l) For a given value of principal quantum number, the value of azimuthal quantum number ranging from 0 to (n-1). n l l = 0 1 2 3 4 1 0 Designation = s p d f g 2 0,1 3 0,1,2 4 0,1,2,3 Magnetic quantum number ★ The magnetic quantum number determines the number of preferred orientations of the electrons present in a subshell. ★ As each orientation corresponds to an orbital , therefore the magnetic quantum number determines the number of orbitals present in any subshell. Magnetic quantum number ❏ The magnetic quantum number is denoted by m or ml . ❏ For a given value of l, magnetic quantum number can have all the values ranging -l to +l . Total values of m =2l+1 Spin Quantum number(ms) This quantum number helps to explain the magnetic properties of the substances. A spinning electron behaves like a micromagnet with a magnetic moment. If an orbital contain two electrons, the two magnetic moment opposes and cancel each other. Spin Quantum number Important points about quantum numbers : ● These are the four quantum numbers. NUMBER SYMBOL POSSIBLE VALUES Principal quantum number n 1, 2, 3, 4, ……. Angular momentum quantum l 0, 1,2,3, ……..(n-1) number Magnetic quantum number ml -l , ……… , -1, 0, 1,......, l Spin quantum number ms +½, -½ Important points about quantum numbers : To sum up the four quantum numbers provide the following informations about orbitals : ● n describes the shell , determines the size of the orbital and also to the extent the energy of the orbital. ● l describes the subshell and the shape of the orbital . There are n subshells in nth shell . To some extent , l also determines the energy of the orbital in a multi electron atom. ● ml designates the orientation of the orbital . For a given value of l,m , can have (2l+1) values or number of orbitals . ● ms refers to the orientation of the spin of the electron. MASTER CLASS TEACHER TEACHER Post-class: doubt solving More than 2 Million doubts solved Assessment: regular tests Enroll into Multiple course How to Avail Discount ? Special Discount for this class Apply Coupon Code: MRPRO Visit: https://vdnt.in/YTPRO Link in Description Join Vedantu JEE Telegram channel NOW! Assignments Notes Daily Update https://vdnt.in/jeepro .
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