(a) Continuous and line spectrum: The spectrum which consists of all the wavelengths is called continuous spectrum. CBSE Notes for Class 11 Chemistry Maths Notes Physics Notes Biology Notes. Candidates who are ambitious to qualify the CBSE Class 11 Chemistry with good score can check this article for Notes. In this second unit of class 11 chemistry, we will learn the discovery of subatomic particles- electrons, neutrons, & protons, atomic models of J.J Thomson's, Rutherford's, Bohr's. PLANCK'S QUANTUM THEORY . 1. The maximum number of electrons in s subshell is 2, p subshell is 6 d subshell is 10 and f subshell is 14. Half-filled and completely filled electronic configurations are more stable Hence. it emits a radiation of definite frequency (or wavelength). Question from very important topics is covered by Exemplar Questions for Class 11. (b) Isobars Species with same mass number but different atomic number are called isobars. Electrons and the nucleus are held together by electrostatic forces of attraction. Now that the dual nature of light as "both a particle and a wave" has been proved, its essential theory was further evolved from electromagnetics into quantum mechanics. E = hv = hc / λ. where, h = Planck’s constant = 6.63 x 10-34 j-s. E = energy of photon or quantum. (ii) The unpaired electrons present in the various orbitals of the same subshell should have parallel spins. Electromagnetic Radiation It is a form of energy that can propagate in vacuum or material medium and shows both wave like and particle like properties. Planck explain the distribution of intensity of the radiation from black body as a function of frequency or wavelength at different temperatures. It is denoted by v (nu). When these electromagnetic radiations are arranged in order to their increasing wavelengths or decreasing frequencies, the complete spectrum obtained is called electromagnetic spectrum. Only some of the α-particles suffered large deflections, which means that the positively charged mass must be occupying very small space. Threshold frequency (vo) = minimum frequency of the radiation, Work function (Wo) = required minimum energy of the radiation, [Kinetic energy of ejected electron = h(v – vo), where; v = frequency of incident radiation. Q. These question will help you check your preparedness and clear your doubts. Particle Nature of Electromagnetic Radiation. Particle Nature of Electromagnetic Radiation : Planck’s Quantum Theory. (a) Positron Positive electron (0+1e), discovered by Dirac (1930) and Anderson (1932). How does the momentum of a photon change if the wavelength is halved? In this article we will discuss Max Planck’s quantum theory of radiation or quantum theory of radiation, black body radiation, electromagnetic radiation, evidences for a particle theory of energy. Dual behavior of electromagnetic radiation: When a white light is passed through a prism, it splits into a series of coloured bands known as spectrum. Neils Bohr proposed his model in 1931. The theory of light being a particle completely vanished until the end of the 19th century when Albert Einstein revived it. Explain Plancks Quantum Theory. Entire mass of the atom is concentrated inside the nucleus. These travel in straight line away from cathode and produce fluorescence when strike the glass wall of discharge tube. Negatively charged particle discovered on the basis of ‘cathode ray discharge tube’ experiments. Well, Planck was basically the father of quantum mechanics. Here we have provided Exemplar Problems Solutions along with NCERT Exemplar Problems Class 11. It is unable to explain the spectrum of atom other than hydrogen like doublets or multielectron atoms. (d) Anti-proton It is negative proton produced by Segre and Weigand (1955). This article provides you the revision notes on Class 11 Chemistry: Chapter- Structure of Atom, to give you a quick glance of the chapter. Dual Nature of Radiation and Matter MCQ Questions with Answers Pdf Question 1. The radiant energy is emitted or absorbed not continuously but discontinuously in the form of small discrete packets of energy called ‘quantum’. In the case of light, the quantum is known as a photon. In 1905, Einstein applied Planck's quantum theory of light to account for the extraordinary features of the photoelectric effect. Explain planck's quantum theory In the Newtonian era of nineteenth century, an electromagnetic radiation is believed to be exclusively a waveform, as it has no mass. Get all questions and answers of Structure Of Atom Plancks Quantum Theory of CBSE Class 11 Science Chemistry on TopperLearning. Exemplar Questions Class 11 is a very important resource for students preparing for the Examination. 3. Ψ can he positive or negative but ‘I’:? The older Planck played an early and crucial role in the establishment of quantum physics, with his introduction in 1900 of the famous Planck black-body radiation law, or simply Planck’s Law. In the absence of electric or magnetic field these travels in strait lines. Neutral particles discovered by bombarding a thin sheet of beryllium by α- particles. Using particle or quantum nature of radiation we can explain the phenomenon of photoelectric effect and Crompton effect. (c) Meson Discovered by Yukawa (1935) and Kemmer. To simplify our discussion, consider a particle that can have only two possible states. Particle Nature of Electromagnetic Radiation: Planck’s Quantum Theory • An ideal body, which emits and absorb radiation of all radiation uniformly, is called a black body and radiation emitted by such a body is called black body radiation. Velocity of light is 3 * 1010 cms-1. (d) Isodiaphers Species with same isotopic number are called Isodiaphers, e.g., 19K39, 9F19. when an electron jumps from ground states to excited state. Hope these notes will helps you understand the important topics and remember the key points for exam point of view. Atom is made of electron, proton and neutrons. Candidates can click on the subject wise link to get the same. Answer the following questions to check your preparedness: Q. Even before we entered the information age, it was recognized that material objects and the photons of electromagnetic radiation are, in essence, carriers of information. All electrons of nd and nf orbital contribute σ = 0.35 and those of (n – 1)and f or lower orbital contribute σ = 1.00 each. Exemplar Problems solutions along with NCERT Exemplar Problems Class 11 be emitted or absorbed as integral multiple this! ( s. p, d or ( orbital or absorbed as integral of... 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