More from Anunay sharma

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www.tiwariacademy.com, , (1) Atom (Given by Dalton) : Matter is made up of extremely small particles, which are indivisible in nature. It consists of subatomic particles electron,, proton and neutrons knows as FUNDAMENTAL PARTICLES., (2) Electron (Named by Stoney) : Discovered by Cathode Ray experiment, [In CROOK’S TUBES]. A long glass tube with two metal electrodes. At, every low pressure when high voltage is applied a ¯ow is produced due, to ¯ow of – ve charge particle [KNOWN AS ELECTRON], cathode rays., Cathode rays have – ve change, travel in straight lines have electric and, magnetic ®eld have heating effect more penetrating effect., Charge on e– was found by OIL DROP experiment [MILLIKAN]., (3) Proton (Discovered by GOLDSTEIN in ANODE RAY EXPT : in a, perforated cathode tube with gas at low pressure high voltage was passed, b/w electrode rays from cathode produced green FLOURESCENCE on, ZnS wall. These were called as ANODE RAYS. They travel in straight, line, with + ve charge, get de¯ected in electric and magnetic ®eld., (4) Neutron : Fundamental particle which carries no charge but has mass, equal to N atom or PROTON. Discovered by JAMES CHADWICK., Name of, , UNIT, , Electron, , Proton, , Neutron, , amu, , 0.000546, , 1.00728, , 1.008665, , Kg, , 9.109 × 10–31, , 1.673 × 10–27, , 1.675 × 10–27, , Coloumbs, , 1.602 × 10–19, , + 1.602 × 10–19 Zero, , esu, , – 4.8 × 10–10, , + 4.8 × 10–10, , Zero, , Relative, , –1, , +1, , Zero, , Constant, Mass, Charge, , (5) J.J. Thomson : The sphere of + ve change nucleus model of atom is, Atomic Structure, , 13

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balanced by coloumbic force of attraction of e–. Like a Raisin Pudding, Model., (6) Ruther Ford (Discovery of nucleus) :, bombared on gold foil., , particles (+ ve charge), , (a) 99.9% passed without de¯ection : Most space inside the atom is empty., (b) Only few de¯ected therefore mass of atom centrally placed called, nucleus, (c) very few de¯ected back therefore mass of atom contains + ve change, particles [Protons]., (d) Atom is electrically neutral hence – ve change particles placed outside, the nucleus and have very less mass., Limitations : No distribution and energies of e– considered, could not, explain e– does not fall into the nucleus or not; no details of line spectra, of H atom., (7) (a) Atomic number (Z) : The no. of protons or electron in a neutral atom, or, No. of protons in an atom, , (or ion)., , (b) At mass no. (A) : Total no. of protons and neutron in an atom, A = No. of (P + n), , A – Z = No. of neutrons, , (8) (a) Isotopes : Atoms of same element with different mass no., (b) Isobars : Atoms of different element with same mass no., (c) Isotones : Atoms of different element with same no. of, neutron, (d) Isoelectronic : Atoms, molecules or ions with same no. of e– [Ne; O2–]., (9) Electromagnetic radiations : Energy emitted from any source (in forms, of waves) in which electric and magnetic ®elds oscillated perpendicular to, each other and travelling with a velocity to light is known as EM radiation., (10) Characteristics of waves :, (a) Wavelength : the distance of one crest and, one trough in a wave. Denoted by ‘’., (b) F r e qu en cy : n o. of wa ve s p as s i n g, through a given point in one second., , 14, , Chemistry Class XI

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Denoted by ., (c) Amplitude : The height of crest or depth of a trough denoted by ‘a’., (d) Wave no. : No. of waves per unit length denoted by, =, , (or m–1), , (e) Velocity : Linear distance travelled by a wave in one second., velocity of light c, , ,  , ,  , , =, , =, , , , =, , (10) Energywise order for EM radiation., cosmic <  rays < X rays < uv < VIBGYOR < IR < Microwaves < Radiowaves, , , , , ,  Inc., ,  Dec., , Dec., , Energy Dec., , (11) Proton : A packet or particle of light energy is knows as Photon., (12) Planck’s quantum theory : The energy emitted from a source or absorbed, by a source is not continuous but discontinuous in form of small packet, of energy [for light each packet is known as photon], Energy [emitted or absorbed] by a photon  (frequency), E or E = h[h = Planck’s constant], = 6.626 × 10–34 J sec, If ‘n’ photons are emitted E = nh, (13) Photo electric effect : The phenomenon of ejection of electrons from a, metal surface when a light radiation of suitable frequency falls on metal, surface., h = h0 +, h Light radiation falling upon metal surface., h0 Energy used for work function or [Energy for removing e– from, metal],  K. energy by which e– is emitted from metal surface., Atomic Structure, , 15

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(a) Large atoms have less work function., e– emitted with more velocity., (b) Small atoms have more work function., , , e– emitted with less velocity., , Debroglie equation : All material particles possess both matter should also, exhibit wave like properties. Wave character as well as wave character as well, as wave character., , , , , , , , , For microscopic particles mass is very less therefore ‘’ more and more, wave character., For macroscopic particles mass is large  is less therefore more particle, character., Dual behaviour, Heisenberg's Uncertainty Principle, It is impossible simultaneously to determine the exact position and exact, velocity of a subatomic particle., , , , , x × mv, , , , , , , , x = uncertainty in position, , , , , , v = uncertainty in momentum, , For microscopic (mass very less) certainty in position is less therefore x, is more v is less., For macroscopic (large mass) certainty in position is more x is less v, is more., Bohr’s theory for H [H like one e– systems He+; Li2+], (1) e– revolving round the nucleus in circular path [stationey state; SHELL], with a de®nite angular momentum, energy, , 16, , [n no. of shell of e–] and with de®nite, ,  – 2.18 × 10–18, , Chemistry Class XI

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(2) As n increases, Z Decreases Energy of e– becomes  less – ve [Due to less, force of Proton attraction], As n Decreases Z increases Energy of e– becomes More – ve [Due to more, force of attraction by protons], (3) In in®nity shell e– has zero force of attraction therefore zero energy., (4) Electron energy only changes by de®nite values E = Ef – Ei., = 2.18 × 10–18, =, , =, Rydberg constant, Hydrogen spectrum : When e– in hydrogen atom is provided energy it gets, excited to higher shell from ground state, it comes back to ground state by, emitting energy in de®nite values., “Quanta” : The emission of light energy is known as emission spectra. It, corresponds to each atom depending upon which energy shell e– is excited., It is discontinuous spectra as ‘’ of light radiations do not merge with each, other like is VIBGYOR (Continous Spectra)., When e– falls from any excited state to, = 1,09,678, (a) Ist energy level nf = 1, ni = 2, 3, 4, .... [Lyman series] (UV), (b) When e– to ®nal state n = 2, ni = 3, 4, 5, .... [Balmer series] (VIBGYOR), (c) When e– to falls to ®nal state 3 ni = 4, 5, 6 [Paschem series] IR., (d) When e– to falls to ®nal state 4 ni = 5, 6, 7 [Bracket series] IR., (e) When e– to falls to ®nal state 5 ni = 6, 7, 8 [Pfund series] IR., Quantum numbers : The no. which completely de®ne the state of e–., Atomic Structure, , 17

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(a) Position and energy of e– (b) Path of e– (c) Orienation in space (d) Rotational, motion of e–. These are described by four quantum numbers., (1) Principal Q. No. : It describes the distance of e– from nucleus ‘n’ i.e.,, de®nes the shell no. It is denoted by ‘n’., n, , = 1, 2, 3, 4, 5, ....., K, L, M, N, O ....., , (2) Azimutha Q. No. : It de®nes the path of e– decided by angular momentum, of e–. Each angular momentum value corresponds to one subshell. The, no. of subshells in a shell is 0 to n – 1., n, , l (0 to n–1), , 1, , 0, , l=0, , ‘s’, , subshell, , 2, , 0, 1, , l=1, , ‘p’, , subshell, , 3, , 0, 1, 2, , l=2, , ‘d’, , subshell, , 4,, , 0, 1, 2, 3, , l=3, , ‘f ’, , subshell, , All subshells are wave functions for locating e–., In the same shell energy wise S < P < d < f., (3) Magnetic Q. No. : It gives the no. of magnetic orientations an e– can have, in a subshell. The no. of magnetic orientation an e– can have in a subshell,  – l to 0 to + l., (4) Spin Q. No. : An e– is continuously spinning on its own axis. This Q. No., describes e– can have clockwise spin motion, anticlockwise spin motion, , or e– can have, , . An orbital can have mximum two e–, , one with clockwise and other with anticlockwise spin., Aufbau principle, (a) e– are ®lled in increasing order of energy of subshell., (b) As ‘n + l’value inc. energy of e– increases in that subshell., (c) For two subshells with some ‘n + l’ value. As ‘n’ value increases energy, of e– increases., Pauli’s principle, No two e– can have same set of 4 quantum nos. If two e– are present in, 18, , Chemistry Class XI

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STRUCTURE OF ATOM, A. Fundamental particles of an atom, Electromagnetic Spectrum &, Bohr’s Theory, 1-Mark Questions, Q. 1., , Give the difference in the origin of cathode and anode rays., , Q. 2., , Which of the following will not show de¯ection from the path on, passing through an electric ®eld ? Proton, electron and neutron., , Q. 3., , Neutron or proton of same wavelength, which will have more, velocity ?, , Q. 4., , Chlorophyll absorbs radiations of wavelength 700 nm. What is the, frequency of this radiation ?, [Ans.4.2 × 10s Hz], , Q. 5., , If the length of the crest of a wave is 4 pm. Write the wavelength of, this wave., [Ans.8 pm], , Q. 6., , Arrange the following in the increasing order of their e/m values., electron, proton and neutron., , Q. 7., , A radiation emitted from a hot iron is photon or quantum ?, , Q. 8., , Give two examples from everyday life where cathode rays tube used., , Q. 9., , The line spectrum of an element is known as ®ngerprints of its atom., Comment, , Q. 10. An element lias atomic number 30 and mass number 66, what will, be the number of protons and neutrons in this atom?, [Ans.protons = 30 & neutrons = 36], Q. 11. Calculate the mass and charge of one mole of electrons. [Ans.5.48 × 10–4 g], Q. 12. Calculate the charge of one mole of electrons., , [Ans.9.6488 × 104 C], , Q. 13. What is the value of the Bohr’s radius for the ®rst orbit of hydrogen, atom ?, Q. 14. Distinguish between a photon and a quantum,, Q. 15. What type of metals are used in photoelectric cell ? Give one example., [Ans.With large size less work function.], Q. 16. Write the number of electrons present in 1 mol. of N3– ion., Q. 17. Write the difference between atomic mass and atomic mass number ?, 20, , Chemistry Class XI

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Q. 18. Which series of lines of the hydrogen spectrum lie in the visible region ?, Q. 19. Cs show maximum photoelectric effect, why ?, Q. 20. CI and CI– have same atomic number or mass number or both. Explain., 2-Mark questions, Q. 1., , How could Rutherford in his experiment explain Nucleus ?, , Q. 2., , De®ne black body and black body radiations., , Q. 3., , Give the essential postulates of Bohr’s model of an atom. Howdid it, explain ?, (i) the stability of the atom ?, (ii) origin of the spectral lines in H-atom ?, , Q. 3., , What is quantisation ? How quantisation of energy was introduced, in Bohr’s model ?, , Q. 4., , An element with mass number 81 contain 31.7% more neutron as, compared to protons., [Ans.81Br], , Assign the atomic symbol., Q. 5., , What transition in the hydrogen spectrum would have the same, wavelength as the Balmer transition n = 4 to n = 2 of He+spectrum?, [Ans. n1 = 1 and n2 = 2], , Q. 6., , What transition of Li2+ spectrum will have the same wavelength as, that of the second line of Balmer series in He+spectrum ?, [Ans. n2 = 6 to n1 = 3], , Q. 7., , Calculate the energy required for the process, He+(g) ——, , He2+ (g) + e–, , The ionization energy for the H atom in the ground state is 2.18 ×, 10–18 J atom–1], [Ans. 8.72 × 10–18 J], Q. 8., , Calculate the wave number for the longest wavelength transition in, the Balmer series of atomic hydrogen., [Ans. 1.523 × 106 m–1], , Q. 9., , To which orbit the electron in H atom will jump on absorbing 12.1, eV energy ?, [Ans. 3rd orbit], , Q. 10. Calculate the energy associated with the ®rst orbit of He +. What is, the radius of this orbit., [Ans. – 54.38 eV, 0.2645 Å], Atomic Structure, , 21

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Q. 11. What is the distance of separation between 3rd and 4th orbit of, H-atom ?, [Ans. 3.703 Å], Q. 12. The energy of electron in the ®rst Bohr’s obit is – 13.6 eV. Calculate, the energy of electron in the ®rst excited state., [Ans. – 3.4 eV], Q. 13. Calculate the number of protons emitted in 10 hours by a 60 W sodium, lamp emitting radiations of wavelength 6000 Å., Q. 14. Which one has a higher energy, a photon of violet light with wavelength, 4000 Å or a proton of red light with wavelength 7000 Å ?, [Given. h = 6.62 × 10–34 J sec.], Q. 15. A 100 watt bulb emits monochromatic light of wavelength 400 nm., Calculate the number of protons emitted per second by the bulb., [Ans. 2.012 × 1020 s–1], Q. 16. What is the maximum number of emission lines when the excited, electron of a H atom in n = 4 drops to the ground state ? [Ans. 6], Q. 17. Which has more energy, light radiation of wavelength 400 Pm or light, radiation of frequency 1015 Hz ?, Q. 18. Find the energy of electron in 4th shell of Li2+ ion., Q. 19. What is the wave number of an electron with shortest wavelength, radiation in Lyman spectrum of He+ ion., Q. 20. Write short note on :, (a), , Continuous and discontinuous spectrum., , (b), , Absorbtion and emission spectrum., 3-Mark Questions, , Q. 1., , How were cathode rays discovered ? With the help of suitable, experiments show that :, (i), , Cathode rays tavel in straight lines,, , (ii), , Cathode rays consists of material particles,, , (iii) Cathode rays consists of negatively charged particles., Q. 2., , 22, , Write the complete symbol for :, (i), , the nucleus with atomic number 56 and mass number 138., , (ii), , the nucleus with atomic number 26 and mass number 55., , Chemistry Class XI

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(iii) the nucleus with atomic number 4 and mass number 9., Q. 3.(i) The energy associated with the ®rst orbit in the hydrogen atom is, – 2.18 × 10–18 J atom-1. What is the energy associated with the fourth, orbit ?, (ii) Calculate the radius of Bohr’s third orbit for hydrogen atom., [Ans.– 1.36 × 10–19 J atom–l .4.761 nm], Q. 4., , A bulb emits light of wave length 4500Å. The bulb is rated as 150, watt and 8% of the energy is emitted as light. How many photons are, emitted by the bulb per second ? [H.O.T.S1, [Ans. n = 27.2 × 1018], , Q. 5., , When light with a wavelength of 400 nm falls on the surface of sodium,, electrons with a kinetic energy of 1.05 × 105 J mol-1 are emitted., , (a) What is the minimum energy needed to remove on electron from, sodium ?, (b) What is the maximum wavelength of light that will cause a, photoelectron to be emitted ?, [Ans. a = 3.2255 × 1019 J, b = 616 nm], Q. 6., , Compare the frequency of light radiations emitted when electron falls, from 5th shell to the 2nd shell in Li2+ ion and electron falls from 4th, shell to the 1st shell in He+ ion., 5- Mark Questions, , Q. 1.(a) De®ne Photoelectric effect ? Mention its one practical application in, daily life,, (b) Electrons are emitted with zero velocity from a metal surface when, it is exposed to radiation of wavelength 6800 Å. Calculate threshold, frequency (o) and work function (Wo ) of the metal., [Ans. o = 4.41 × 1014 s–1 Wo = 2.92 × 10–19 J], Q. 2.(a) The electronic energy in Bohr’s orbit is negative .How will you account, for it, (b) The ionisation energy of hydrogen atom is 13.6 eV. What will be the, energy of the ®rst orbit of He+ and Li2+ ions ?, [Ans. E1 of He+ = – 54.4 eV, E1 of Li2+ = – 122.4 eV ], Q. 3.(a) De®ne the following terms :, (i), , Threshold frequency, , (ii) Work function., Atomic Structure, , 23

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(b) The work function for Cs atom is 1 .9 eV. Find threshold wavelength, (0)and threshold fequency (0) of this light radiation. If Cs metal is, irradiated with a radiation of wavelength 500 nm ®nd kinetic energy, and velocity of emitted electron., , Dual Nature of Matter, de Broglie Equation,, Heisenberg’s uncertainty principle and wave, mechanical model, 1 - Mark Questions, Q. 1., , Mention the physical signi®cance of  and 2., , Q. 2., , Why did Heisenberg replaces the concept of de®nite orbit by the, concept of probability ? (e– with very less mass more as wave), , Q. 3., , What is uncertain in uncertainty principle ?, , Q. 4., , Can a moving cricket ball have a wave character ? Justify your answer., , Q. 5., , Heisenberg uncertainty principle has no signi®cane in our everyday, life. Explain., , Q. 6., , Out of the d orbitals which does not have four lobes ?, , Q. 7., , Write the Schrodinger wave equation., , Q. 8., , Why uncertainty in position is more when uncertainty in velocity is, less for an electron ?, 2-Mark Questions, , Q. 1., , Calculate the mass of the photon with wavelength of 3 .6 Å., [Ans. 6.135 × 10–29 kg], , Q. 2., , Calculate the mass of the photon with wavelength of 5 Pm., , Q. 3., , On the basis of uncertainty principle show that an electron cannot, exist with in atomic nucleus., (Given : Nuclear radius = 10–I5 m), [Hint : Taking 10–15 m as x, the v comes much higher than the, velocity of light and hence is not possible], , Q. 4., , Explain why the uncertainty principle is signi®cant only from the, motion of subatomic paricles and is negligible for macroscopic, particles., , Q. 5., , List two differences between orbit and orbital ., , Q. 6., , Show that the circumference of the Bohr orbit for the hydrogen atom, , 24, , Chemistry Class XI

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is an integral multiple of the de Broglie wavelength associated with, the electron revolving around the orbit, Q.7., , Comment on “Bohr’s model is against the Heisenberg uncertainty, principle”., , Q. 8., , What are the similiarties and difference in 2s and 2px orbitals and 1s, and 2s orbitals ?, , Q. 9., , Give three differences between 3p and 4p subshell., 3-Mark Questions, , Q. 1., , Calculate the number of waves made by Bohr electron in one complete, revolution in its third orbit., [H.O.T.S] [Ans. 3], , Q. 2., , What should be the ratio of velocities of CH4 and O2 molecules, so that they are associated with de Broglie waves of equal, wavelength ?, [Ans. 2], , Q. 3., , Calculate the wavelength of an electron that has been accelerated in, a particle accelerator through a potential difference of 1 kv., [Given 1eV = 1.6 × 10–19 J], , [H.O.T.S] [Ans. 3.87 × l0–7 m], , Q. 4.(i) Discuss the similiarities and differences between a 1s and 2s orbital., (ii) Draw the shape of dz2., Q. 5., , Calculate the wavelength of a tennis ball of mass 60 gm moving with, a velocity of 10 m per second., [Ans. 10–3 metre], , Q. 6., , Calculate the wavelength of 1000 kg rocket moving with a velocity, of 3000 Kilometre per hour., [Ans. 7.9512 × 10–40 m], , Q. 7., , Calculate the uncertainity in the velocity of a cricket ball of mass 150, g, if uncertainity in its position is of the order of 1 Å., [Ans. 3.5 × 10–24 m s1], , Q. 8.(a) What is de-Broglie wavelength for an electron with light velocity?, (b) What is the angular monemtum of electron in 5th shell., Q. 9., , Two particles A and B have wavelength A = 5 × 10–10 m and B =, 10 × 1010 m. Find their frequency, wave number and energies. Which, has more penetrating power and why ?, , Q. 10.(a)Which has max. uncertainty regarding position and why ?, Electron, proton and neutron., Atomic Structure, , 25

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(b) Find the number of waves associated with a light radiation of time, period 5 ns., Q. 11. If an electron in He+ has angular momentum of 5h/2. Find its energy, and wavelength associated with it. Find the kinetic energy of this, electron., 5-Mark Questions, Q. 1.(a) State de Broglie equation. Write its signi®cance., (b) A beam of helium atoms moves witha velocity of 2.0 × 103 m s–1., Find the wavelength of the particle constituting the beam, (h = 6.626 × 10–34 J s) [Ans. 49.9 pm ], Q. 2.(a) State Heisenbergs uncertainty principle. Give its mathematical, expression. Also give its signi®cance., (b) Calculate the uncertainity in the position of a dust particle with mass, equal to 1 mg if the uncertainity in its velocity is 5.5 × l0–20ms–1., [Ans. 9.55 × 1010 m], Q. 3.(a) Cricket ball, a tennis ball and a proton which has more uncertainity, in velocity and which follows Heisenberg uncertainity principle, maximum., (b) Whet is same in de-Broglie and Heisenberg principle, which is differnt, from Bohr theory for structure of atom., (c) Why Schrondinger wave only de®nes electron path uncertain but, de®nite energy., , Quantum Numbers, Electronic, Configuration and Nodes, 1 Mark Questions, Q. 1., , What is the lowest value of n that allows g orbitals to exist ?, , Q. 2., , What are the four quantum numbers of 19th electron of copper ?, (Ans. Atomic number = 29), , Q. 3., , Which quantum number is not obtained from solution of Schrondinger, wave equation ?, , Q. 4., , How many electrons will be present in the sub-shells having ms, value, of – 1/2 for n = 4 ?, , 26, , Chemistry Class XI

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Q. 5., , Write the electronic con®guration of Ni 2+. (At. no. of Ni = 28), , Q. 6., , How many radial and angular nodes are present in 2p orbital., [Ans. Radial nodes = 0, Angular nodes = 1], , Q. 7., , Which of the following orbitals are possible ?, 1p, 2s, 2p and 3f., , Q. 8., , Write the name of non-directional orbital., , Q. 9., , Write the name of quantum numbers which determines the orientation, of orbital and shape of orbitals., , Q. 10. Write the name of quantum number which determines the shape of, orbital., Q. 11. Using s, p, d notations, describe the orbital with the following quantum, numbers :, (a) n = 4, 1 = 2 (b) n = 1, l = 0., , [Ans. (a) 4d (b) 1s], , Q. 12. How many orbitals are presenting subshell ?, Q. 13. How many total electrons can be filled in all orbitals with, (n + l) = 5 ?, [Ans. 18 electrons (4p6 3d10 5s2], Q. 14. Name the dipositive ion represented by the electronic con®guration, : 1s2 2s2 2p6 3s2 3p6., [Ca2+], Q. 15. Is it correct to say that every atom with even atomic number has all, electron paired ?, Q. 16. Cr in ground state has how many unpaired electrons., (Cr, Atomic number = 24)., Q. 17. Which has more energy of electron 4p or 5s ?, Q. 18. Nitrogen has correct con®guration of 1s2, 2s2, 2px1,2py1, 2pz1 is, described by which principle ?, Q. 19. Whal are degenerate orbitals ?, 2-Mark Questions, Q. 1., , On the basis of Pauli’s exclusion principle show that the maximum, number of electrons in the M -shell (n = 3 ) of any individual atom, is 18., , Q. 2., , Designate each subshell with n = 4., Atomic Structure, , 27

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Q. 3., , List the possible values for all the quantum numbers for the following, subshell., (a) 2p, , (b) 4f, , Q. 4., , Write down the elctronic con®guration of Fe3+ and Ni2+. How many, unpaired electrons are present ? (Atomic number, Fe = 26, Ni = 28), , Q. 5., , Out of principal, angular, magnetic and spin quantum number, which, quantum number determines the ?, (a), , Shape of the orbital, , (b), , Number of orbitals in an orbit, , (c), , Size of the orbital, , (d), , Spin orientation of the electron., , Q. 6., , What is the Hund ‘s rule of maximum multiplicity ? Explain with, suitable example., , Q. 7., , Explain why :, , Q. 8., , Q. 9., , (a), , The three electron present in 2p subshell of nitrogen remain, unpaired, , (b), , Cr has con®guration 3d5 4s1 and not 3d4 4s2., , (a), , 4p1 and 4p2 electron will have same (i) n, l, m or (ii) n, l, s or, (iii) n, l, m, s, or n, 1, , (b), , Nitrogen has 7 proton, 7 electron and 7 neutrons. Calculate the, number of electron protons and neutrons in N3– ion., , Which has more energy of electron :, (a), , Last electron of Cl– or last electron of O2–., , (b), , n = 4, l = 3 or n = 5, l = 2., 3-Mark Questions, , Q. 1.(i) An atomic orbital has n = 2. What are the possible values of l and m1 ?, (ii) List the quantum numbers (m1 and l) of electrons for 3d orbital., (iii) Which of the following orbitals are possible ?, 2d, 1s, 2p and 3f., Q. 2.(a) Write the maximum nunber of electron in a subshell with l = 3 and, n = 4., 28, , Chemistry Class XI

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(b) Write the maximum number of electron that can be associated with, the following set of quantum numbers ?, [n = 3, l = 1 and m1 = – 1], (c) Write the maximum nunber of electron that can be accomadated in, an atom in which the highest principal quantum number value is 4., Q. 3.(i) Write the electronic con®gurations of the following ions :, (a) H– (b)Na+ (c)O2– (d) F–, (ii) What are the atomic numbers of elements whose outermost electrons, are represented by (a) 3s1(b) 2p3 and (c) 3p5 ?, (iii) Which atoms are indicated by the following con®gurations ?, (a) [He] 2s1 (b) [Ne] 3s2 3p3 (c) [Ar] 4s2 3d1., Q. 4., , Calculate:, (a), , Total number of spherical nodes in 3p orbital., , (b), , Total number of Nodal planes in 3p orbital., , (c), , What is nodal planes in 3d orbital,, 5-Mark Questions, , Q. 1.(a) Write short notes on:, (i) Aufbau principle (ii) Pauli’s principle (iii) Hund’s rule., (b) Write the electronic con®guration of the following ions :, (i) Fe3+ (ii) Cu+, 26 & 29], , [Atomic number of Fe and Cu are, , Q. 2.(a) Draw the shapes of the following orbitals., (i) 3dxy (ii) dz2, (b) What is the total number of orbitals associated with the principal, quantum number n = 3 ?, (c) Using s, p, d, f notations, describe the orbital with the following, quantum numbers., (a) n = 3, l = 0, (b) n = 4, l = 2, (c) n = 5, l = 3, (d) n = 1, l = 0, Q .3., , Explain the following :, (i), , Energy of electron is not decided by : n, l ,m and s., Atomic Structure, , 29

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(ii), , Maximum number of electron with – 1/2 spin for n = 3 is 6,9,12, or none., , (iii) Maximum number of electron can be present for n + l = 4., (iv) 3f subshell is not possible., (v), , Maximum number of electrons in a subshell is :, (2l + l) or (4l + l) or n2, , Q. 4.(a) A neutral atom has 2K, 8L & 15 M electrons. Find the total numbers, of electrons in s, p, d and f subshell., (b) How many unpaired electrons are present in the following ions :, Al+, Cr2+, Co3+ and Mn2+, (Atomic number : Al=13, Cr = 24, Co = 27 & Mn = 25), (c) One electron is present in 4f subshell. What is the sum of n + l +, m1 + ms values assuming ‘f ’ subshell follows – 3 to + 3 order of, ®lling electron., Q. 5., , Write the :, , (a) n + l value for 14th electron in an atom., (b) Increasing order of ®lling electron in 4f, 5p and 6d subshells., (c) ‘m’ and ‘l’ value for last electron of Mg atom., (Mg atomic number is 12), (d) Subshell in which last electron is present in Ga., (Atomic number is 31), (e) Sum of spin of all the electron in atomic number 14., , 30, , Chemistry Class XI