ElectronGate

Hello What's up..😊😊😊 [2]Azimuthal quantum numbers (l) It denotes the energy associated  with the angular momentum of the electron. it is also quantized and is indicated by— These values Indicate the sub-shell. The value of l vary from l = 0   to  l = (n -1) It  denotes actually    The shape of an electron orbital.     [3]  Magnetic quantum number (m). which Indicates Orientation of  electronic orbit in space under the influence of magnetic field. The value of magnetic quantum number ( m ) depends upon the value of (l).  it may have integral  values from -l to +l  including 0, [4]  Spin  quantum numbers (s). the electron always spins about its own axis either clockwise or anti-clockwise. Spin Quantum numbers gives the information  about the direction  of spinning of electron present in any orbitals. chat summary:

  Quantum numbers :  the concept of quantum numbers was first introduced by Neils Bohr, 1. principal (n)   2. Azimuthal (l)  3. Magnetic  (m)   4.spin  Bohr's model predicts only  one quantum number (n), But the quantum mechanical model of atom introduces three more quantum numbers, As a matter of fact, in order to have a complete knowledge of the energy  states of electron in an atom, four quantum numbers are required.  The size and shape of electron  orbits, orientation  of orbitals in the magnetic field  and the spin of an electrons about its own  axis — are all characterized by a thorough knowledge  of the four quantum numbers. [1.] The principal quantum numbers (n) : • thus " n "  indicates the size of the electron orbit.  • The principal quantum number determines  the energy of the electron present in any shell.  it also indicates how the probability of finding the electron var...

Thus the angular momentum (mvr) of the electron   should  be an integral multiple of h/2π. •Thus angular momentum of an electron is quantized.

●Difference between Orbit and Orbitals :– Video lecture dekhne k lie, YouTube channel ko subscribe kijiye👇👇👇 https://youtu.be/QZODCfNWW0w 1.    Orbit-   it is a definite circular path followed by an electron.  where as  Orbital-    It is a region in space around the nucleus  where the probability of finding the electron is maximum.  2 .  Orbit-  The shape of an orbit is circular or elliptical.     where as Orbital- Different orbitals have  different shapes   e.g.,   s-orbitals are  spherical,  p-orbitals are dumble shaped etc. 3 .   Orbit-  An orbit can have more than two electrons,   an orbit can accommodate maximum 2n² electrons.   e.g  3 rd  orbit (n=3) can accommodate maximum  18 electrons.  where as Orbital- An orbital cannot accommodate more than two electrons. 4 .  Orbit -  Two orbits in an atom cannot ha...

From the various  experiments involving  the Interactions  of light and matter,  Radiation has dual nature i.e it posses properties  of both wave and particles.  photo-Electric effect show that light behaves as particles. where as Young double slit experiment show that light behaves as waves. On examination of Planck's and Einstein's  relationship,  L. de Broglie (1923) concluded  that the  energy is associated with both radiation and matter. De Broglie Hypothesis: A wave is  Associated with a moving material particles which controls a particles  in every respect wavelength =  Planck's constant  / momentum 

    Electromagnetic  waves : According to Maxwell, the electromagnetic waves are those waves in which there are sinusoidal variation of electric  and magnetic field vectors  perpendicular to each other as well as right angles to the direction of waves propagation.  Notes :— these waves do not require any material medium for propagation.  these waves travel in free space with a speed  3×10⁸ m/s ● Since, waves can be produced by moving a charged body or a magnet to and fro in an oscillating manner,  Relation between  frequency and wavelength 

  Wave:— a periodic disturbance of the particles of a substance which may be propagated without net movement of the particles To watch explanation in hindi  (YouTube channel subscribe kjiye)👇👇 https://youtu.be/_zA-UHNXgE4 Wavelength (  λ   ) : It is the distance between the two successive crests or trough of  a wave.   wave number (  ṽ ) : It is defined as the number of waves present in one centimeter length. ( Reciprocal of the wavelength)     wave number =  1/ wavelength  Frequency  (v): It denotes the number of waves passing through a particular point in one second.   frequency = 1/ time Unit : Hertz or   s −1

  Bohr  Model of hydrogen Atom : must subscribe 👇👇 https://youtu.be/uCL36h8wM5Y In view of the limitations of the Rutherford atom model,  Bohr cleverly combined classical ideas and early quantum concepts ( given by Planck ) to give what is  known as Bohr Model of hydrogen atom. following are the  three basic postulates of this model : Every Atom consist of central core, called nucleus.  In which entire +ve charge and almost entire mass of the atom are concentrated. a suitable number of electron revolves  around the nucleus in circular orbit. the centripetal force required  for revolution is provided by electrostatic force of attraction between the electron and the nucleus.  According to Bohr electron can revolve only in certain discrete non radiating orbit called stationary orbit for  which total angular momentum of revolving electron (mvr) is an Integral multiple of h/2 π. where h   planck constant.      3....

  https://youtu.be/F8sk85USIJQ must subscribe this channel🤗 Isotopes:–  Atomic species having the same atomic number (Z)  with different mass number (A). i.e, atomic mass. are called Isotopes. Isotopes  Isobars :– Atomic species having the same  mass number with different atomic number are called Isobars. Isotones :– Atomic species having the same number of neutron but different mass numbers, are called Isotones.

Scattering of Alpha particles by thin metal foil :— https://youtu.be/3b5pEBi69hc The First Idea of atomic model was proposed by E. Rutherford (1911) which was based upon his novel experiment of scattering of Alpha particles by metal foil.  an Alpha emitter was placed in a lead box. A narrow  beam of alpha particles escaped through small hole in the lead box and hit a thin metal foil of gold ( 0.0004 mm thickness) which was placed in the beam of the alpha particles. A circular fluorescent ( zinc sulphide )  screen was set up around the metal foil. A flash of light was observe when the alpha particles hit the screen after penetrating through the thin foil.   Observation  : (1.),  Most of the alpha particles (99.84 %)  passed straight through the foil without any deflection.  (2.)  0.14 %  of alpha particles deviated more than   1° (3.)  1 in 8000 alpha particles deviated more than 90° (4.)    1 in 10⁶ alpha pa...

https://youtu.be/oLhDYRDdNl0 Alpha rays :- Nature: He nuclei represented as    2 He⁴  or He²+ Mass :    4 a.m.u or  6.642 × 10^ –27 kg Charge : Positive charge of +2 units Penetrating power : Minimum -0.1 mm thick aluminum foil can stop it. Ionising power :   Maximum. Beta rays:- Nature: Stream of electron represented as -1e⁰. Mass :    0.000548597 a.m.u. or 9.1 x 10 - 31 kg Charge : Negative charge of –1 unit. Penetrating power : It is stopped by 5 mm thick Aluminum foil. Ionising power : Less than Alpha but more than Gamma rays. Gamma rays:— Nature : Electromagnetic waves of very short wavelengths. Mass : No mass Charge : 0 Penetrating power : Maximum — even 750 mm thick pb plate cannot stop it. Ionising power : very Low.

 The French physicist Henry Becquerel was engaged in furnishing a relation between X-rays and luminescence  exhibited by Uranium salts. Hindi video lecture dekhne k lie  👇👇👇   One day in 1896 by chance he wrapped a photographic plate in a thick black paper and placed a small crystal of potassium uranyl sulphate upon the black paper.Next day to his surprise he saw that the photographic plate had darkened at some places.  Becquerel concluded that the uranium salt had emitted a kind of ray which could penetrate the thick black paper, like X-rays.  Discovery of Radioactivity  After  thorough Investigation on the nature and the characteristics of the rays he came to the following conclusions  :--- 1. Uranium salts spontaneously emitted a kind of that could not be controlled by any physical or chemical condition.  2.  The ray could fog photographic plate wrapped in black paper and could pass through thin sheets of metal foil which are ...

   Around 1879, William Crookes observed that when an electric discharge from high potential source is passed through a gas at 0.001 mm pressure of Hg  in a discharge tube. the glass wall opposite to the cathode began to glow witha very faint greenish light. To watch lecture video on this topic, must subscribe this channel👇👇👇 this glow ir fluorescence  is formed due to the bombardment on the glass by certain rays which are emitted from the cathode surface and move towards the anode with tremendous velocity.    this rays is called Cathode  rays. properties of cathode rays : they are deflected from their original straight line path by the application of both electric and magnetic fields and the direction of deflection  indicates that they consist of negatively charged particles .  they  produce a mechanical motion on small and very light paddle wheel when it is placed in the path of cathode rays. this confirms the presence of material p...