Structure Of Atom Class 11 2022 PDF

SHOBHIT NIRWAN's DESIGNED STRUCTURE OF ATOM NEW NOTES FOR CLASS 11 2022 EXAMS  - Thomson 's Model ( Plum pudding Model ) -...

SHOBHIT NIRWAN's DESIGNED STRUCTURE OF ATOM NEW NOTES FOR CLASS 11 2022 EXAMS  - Thomson 's Model ( Plum pudding Model ) - uniformly distributed in -0 o e are atom ° atom is neutral charge on atom net -0 charge 0 ° net ⑦ve - ve on e-. mass of atom is uniformly distributed °. -0 Drawback around nucleus - e are not stationary they are revolving. 311T IT IS Thomson HIEI fall GT tf Rutherford Chacha story tf 3¥ Fg Rutherford 's Model § scattering experiment : - - observation : ° Most of L particles pass undeflected -. A few particles deflected at some angle g A few ( t.. out of 2000) deflected at 180? as Helium Cueey Conclusion : ° Most of the part of atom is vacant. ° Atom has some ④ve charge in it. ④ re is concentrated in nucleus charge of atomaround °. -0 o e are revolving nucleus. o protons + Neutrons = Nucleons Drawback - He explain stability of atom could not. HI Rutherford Chacha 2A fail Ef tht , HI story tf 34K¥ Bohr -914T but Bohr 919T tit model tTHfH FIAT Etf BUT comets tTH£H ETI l # 318ft 419117 tit model hold YT 2244T the con ceps HIETT E : - Electromagnetic Radiation ↳ when electrically charged particle moves under acceleration , alternating electrical and magnetic fields generated and transmitted in form of are called waves electromagnetic waves , electromagnetic radiation FEMA) or ( L) wave Nature of E. M R. ° According to Maxwell , a accelerated charge particle produce electric and magnetic field. o f and Meg are perpendicular to each other E -. and also I to direction of do not propagation. o E m R -.. require any medium and they can travel in vacuum with speed 3×108 m/s ) of light ( C =  crest → crest → crest → topmost bottommost trough → K3B trough ← → trough CB wavelength Cd) - linear distance b/w two consecutive crest or b/w two consecutive trough It Is generally expressed in terms of. Angstrom CA) [. LAO " ) frequency Ii ) - Lo - - m % - No of waves passing through. a point in one second. SI unit is hertz (Haz) speed velocity µ= →. or - t S - fig velocity Cc ) - linear distance travelled by ware per second 17=47. Cvs wave number.GE! Number of wavelengths per unit length -. - s When the electromagnetic radiations are arrangedobtained in order of their increasing wavelengths decreasing frequencies or , the spectrum is called Electromagnetic spectrum. IP : for the 5000 Ao g calculate wave number and frequency. Eod: Given , DE 5588890 ( staff qhafter E units AT HHT eat ) -. ,o m , I guide calculation ET et HHT wave number (J ) tf Lost ' t gtfo - 2 - m tf units III St solve th - = , M frequency ( Jk " 3f?→m/q t I 6×20 6×10112 - = s or Drawbacks of wave nature of EMR : - ° It cannot explain black body radiation and photoelectric effect. (2) Particle Nature of Erm R : Planck 's Quantum Theory.. energy absorbed are emitted from body not continuously ↳ The gradient but discontinuously in form of Energy packet or quantum. In case of light these packets are called Photons ,. Energy Fof photon 9 frequency **E# e -. ' plank 's constant 6.62×10-34 Is org /E=hV_ his = :.*fE=h§# as we know , HI , These are energy of L photon for n' photons g)E=nhV=nh£M ' so , - -  K'B Is Black Body Radiation : The ideal body that emits and absorbs radiations of all frequencies , is black body and the radiation emitted called a by such body is called black body radiation. % BEEKmission of radiation from black body at diff Temp I.. 472 At given temperature intensity of radiation emitted to a , % with decrease of wavelength reaches the maximum valve at a given , wavelength and then starts decreasing with further decrease of wavelength as shown in graph given below ,. 4% Photo - Electric Effect : ° When ofsufficient energy hits the metal surface photons -0 then e comes out of the metal surface. ° There is no time lag b/w striking of photon and emission of e-0. ° There is a characteristic minimum frequency required called threshold frequency HoH , required Min -0 is called work function two) energy of photon tyre °. more an e |Wo=h# kinetic frequency of photon energy of -010 with increase in ° e. * * E = Wo t KE org hv h Vo t Iz me v2 = EP : when radiation of wavelength of 3.10 nm fall on the surface of electromagnetic sodium , the electrons are em mi Hed with RE Loser Calculate the work function. =. of sodium in terms of e. v. Sof's Given g A = 310 n - m g KE = In 5 ev i Wo = I? We know , E = No + KE HU = Wot KE No = hV - KE No = h II ) - KE 124300*219 = - tis er 4 Iser - 25¥ ⑦ Dual Nature of ein r ;. To explain reflection g refractions diffraction etc g light has been considered. as a wave whereas to explain the photoelectric effect , Einstein considered it to be made up of tiny particles called photons. In other words , light is a kind of radiation exhibits dual behaviour ie wares as well. as particle behaviour Such a ware like as well as particle like nature of radiation. is known as dual nature of radiation.  4313 4) The splitting of light into series of colour bands is known as dispersion and the series of colour bands is called a types spectrum Two of spectrum : B.. Emissions Hea the radiations emitted from : when some source ego from. the sun or by passing discharge through gas at low pressure or by electric a heating some substance to high temperature is passed directly through the prism and then recite red on the photographic plate , the spectrum obtained is called emission spectrum. Depending upon source of radiation , the emission spectra are of two types : continuous and line spectra. E) Absorption spectrum : is like the It negative photographic of an emission spectrum A continuum of. radiation is passed through a sample which absorbs radiation of certain wavelength The missing wavelength. which corresponds to the radiation absorbed by the matter leave dark , spaces in the bright continuous spectrum. Spectral lines of H atom : - - when hydrogen gas at low pressure is taken in the discharge tube and the light emitted on is examined with a passing electric discharge spectroscope , the spectrum obtained is called the emission spectrum of hydrogen. Simple equation for calculation of wavelength of lingmp these In Int = = Re -. er =L oat x 107M". forego - Rs lyman series : 1st line 2 ton =L f. - n- 2nd line - n =3 to n =L Fe. Nt =L fixed tent ' ; hi = 2,3 Y. , - - - - D. last line → A- a ton =L balmer series : 1st line n =3 to n=2 ) → 2nd line → n = 4 to n 2 (fixed) - ng =L - , t ni - 3 , Y , 5 - - - last line → n - - a ton =L Similarly for all series... III The diff b/w the T of 1st line of Balmer series and the last line of Paschen series -. Pen is how much ? -12 for Li Self Bodmer : 1st line Ln =3 to n =D F- I = Rl 35 ( ¥ ¥) - R ca) 19¥ ) RE) - ② Paschen : last Crea lo n =D Rl R ⑤ it =L 3M¥ - = - , difference ② - ⑤ 5yd - R Aye HI finally Ett # III MH TT af F Bohr 919T F model F asf tf I BOHR Model ( Applicable for single electronic species of H, teething Be ete ) postulates : % Electron revolve around the nucleus in a fixed circular path of definite energy called stationary orbits. Is Electron revolve only in those circular paths for which the value of angular momentum is equal to integral multiple of hat radius i. -0 e. of e. *R - MeV 8 = n I ✓ velocity -04 orbit 2 IT man ! of e no. Iii Energy exchange takes place only when electron jumps b/w the orbits. Irs The frequency of radiation absorbed or emitted when transition occurs between two States that differ in stationary energy by AE is given by |V=fnI=EEh/ of lower state El Energy → Ez → Energy of higher state. RB Rutherford Chacha stability explain act at UT Ut but Bohr Hat ¥ that : - Bohr suggested that an electron revolving in a particular orbit cannot radiate energy Therefore emission of radiation is not possible as long as the electron. , remains in one of its energy levels and hence , there is no cause of instability in his model. # Calculation of Boho Radius : According to Bohr 's Model g radius of nth orbit is given by z→ : mud /Vn=OO52z9#n#/ Bohras : - for hydrogen 6=1) , the radius of first stationary state is called as Bohr Radius. Fe. 8=0.0529 n - m is value of Bohr radius. # Energy of an electron : E = - 13.6 (Zzz ) eV - od - 2.18×10+8 (qf ) J HB Why energy of possibleorbits ! the electron in a hydrogen atom has negative sign for all and This is because the energy of electron in the atom is lower than the energy -. of free electron at rest A free electron at rest is an electron that is infinitely. far away from the nucleus i. c free from influence of nucleus and is assigned. the energy value of zero Mathematically g n and thus EEO In this state. =. hydrogen atom is called ionised H atom As the electron gets closer to the nucleus in absolute valve and more and more -. ( as n decreases) g En becomes larger negative. The most negative energy valve is given by n =L which corresponds to the most stable orbit We call this the. slate ground. # Calculation of frequency for a transition : - ↳ The frequency ( ) associated with the absorption v and emission of the photon can be evaluated by using equation : - (÷ 's f 3.29×10 - He and I R2 Hp ht) ' I (calculated above ) = = - K' B In general , the number of emission lines when an electron jumps from Nz level tons level are given by the expression : - Mz ND Cns - - ) n,t t - Z (2. E. ) / Ionisation Energy : Energy required to - remove the eo completely from the atom so as to convert it to Pon a positive. state In =D Simply , The energy absorbed by electron in ground so as to jump to infinity (read. forty g for H If = Eo Es - ÷ -. t ft NY f MY " a s - - - -. Litt ate affair at sit I. E. ¥17 HH ¥1 248×10-18 T Velocity of an electron in any Orbit : - V - Zitlnehze mlsec = 218×106 (F) mlsec frequency of revolutions / Number of revolutions ¥ = , substituting valve of r g - 2ITm#2 2 n 2h LIF Radius of two different orbits in H like sample is 4 R 416 R respectively. find the ratio of frequency of revolution of electron in their 2 orbits. sod :. t÷= VIKKI 42482 = #¥ - ② "" ¥=÷i:¥%:x%T nn÷ ④ ÷=oszaxc 2/2Oo 529 X 2) = MI (he ) 2 Are ! , ¥=Y#r that tu # =L these valves in ② putting ¥ # IT= x. #Hand they ' = I = 18:17 F LI: Calculate energy ratio for 3rd orbit of ion 4 2nd orbit of Betton " - Li. Er e÷÷ :::¥÷÷, ¥ " ' ¥. LIE what are the frequency and wavelength of a photon emitted during a transition from n= 5 state to the n=2 state in hydrogen atom ? 5017. AE - 218×10-1851 ÷ ¥). - = 218×10-185 (¥2 - Iq ) -4.58×10-194 magnitude taking only = - 458×10--193 6.91 X 10MHz F- the 6- 6261110 -34g, de 3.0×108 m/s 434 Cy n m -. 6.911110¥ # limitations of Bohr 's Atomic Model : - apb liable on single e species-0 -0 Only °. ° Doa not explain wave nature of e -. o could not explain the ability of atoms to form molecules by chemical bonds.  de - Broglie Equation ↳ Every associated with it party has a wave , the wavelength of which is de Broglie called - wavelength given by : D= Imu tp = ( p mm ntfudm) - - Heisenberg 's Uncertainty Principle. ↳ We can 't measure exact simultaneously -0 position and velocity of e. Mathematically , Dr xD the 7h44 org DX XD MVD I 41T DH Dvr 7h44 x org M K' B The effect of Heisenberg uncertainty principle is significant only for motion of microscopic objects and is negligible for that of macroscopic objects. LPI A golf ball has of and a speed of 45 Mls If the speed can be mass 40g -. measured within accuracy of 2% , calculate the 'uncertainty in the position. seen uncertainty in velocity, DK 45 x Foo = 0.9ms from heisenberg 's principle , ya = he €Ykgm's " HIT M DV - UX 314×40×10-3 kg XO 9. 46 X IO 33M - L.. # Reasons for failure of the Bohr Model : ° It did not consider the dual behaviour of matter. ° It contradicts Heisenberg uncertainty principle Quantum Mechanics. G The branch of science that deals with dual behaviour of matter ie. nature, is called Quantum mechanics wave as well as particle. # Schrodinger Ware Equation : - On the basis of quantum mechanics , Schrodinger proposed quantum mechanical model of an atom He gave Schrodinger a. wave equation to describe the wave motion of the electron in three dimensional space around the nucleus. Hay = EY Ha is called Hamiltonian operator , E and Y are obtained from solution of Schrodinger wave equation. K' B when Schrodingerlevels equation Is solved for hydrogen atom gives , the solution the possible energy the electron and the can occupy corresponding ware function of Y of election associated with each energy level These quantized. States and corresponding wavefunctions which are characterized by energy a set of three quantum numbers principal quantum number n , azimuthal - number I and quantum magnetic quantum number m. Atomic Orbitals : Ware functions of hydrogen hydrogen or like species with one ( wave function is a electron. mathematical function whose valve depends upon the coordinates of the electron in the atom and does not carry any physical meaning. ⑨ An orbital Ps a region in space around the nucleus where the prob. of finding the electron is maximum. 1 ORBIT ORBITAL ° It is well defined circular path around the o It shows the 3 dimensional space around nucleus in which electron revolve. the nucleus within which the probability -0 o Maxim no of e-0 that an orbit can have is. of finding an e is maximum. given by 2n where n is the no of orbit Max no of electrons that can be occupied by ' m.. o. an orbital is always two. Quantum Numbers ↳ set of 4 numbers which is used to define an electron completely - ng l , me , s n principal quantum number → l→ Azimuthal quantum number. Me → Magnetic quantum number S - spin quantum number. K' B orbit tf sich subs hell giant stfu zigs orbital. circular path around nucleus A Orbit no. ( max m no. of -0 e in any orbit is 2n2) in which e -0 revolve. Sub shell A orbital (orbital have maxm of 2e-0) Region or space around nucleus can where probability of finding an E Ps maximum.  lobe @ density → # Shape of Orbitals : - it , " ° S - orbital - spherical shape o P orbital - - dumb bell- shape Be ¥4, 78... o d- orbitals : double dumb bell - - & 88 88 ay *. , dry dyz dxz density is along -0 the e plane n 't I ⑧ x 800 x da ' ' de y - density is along axis. o f - orbital - complex or deaf type. # # Quantum: (a) Principal Quantum Number In) : - ° It describes shell or orbit. n= I 2 3 4 - - - - shell = K L M N - - - ° no. of sub shell = n ° no. of orbitals = na -0 ° NO. Of e =2n2 (b) Azimuthal Quantum Number (d) °o° It describes subshell. ° Valves d 0 to of n I ' ' = - 1=0 → s I =L ° gives info about shape of orbital IT shape IA at Ffi ). → p ( 4TH Sep d. f TMNT , 1=2 → d 1=3 → f ° Orbital Angular momentum 1=4 → g. 14 # ere = (c) Magnetic Quantum Number :-( Me) ° It describes and orientation shell shape of. valves l Sm Stl o of m: - including zero. II " b- O - m=0 ↳⑤ S ( because l) m f- L → m = - I O, I 1-1 Ix ! ¥ , ↳ cps p me -2 - I O d 2 F- Yd -2, -40,42 It → M= , !y dtdtxzdxtya La d Mes - 3 - 2 - I O L 2 3 1=3 → m =-3 ,-2 , -40,1 , 2,3 _l - ↳ CH (d) spin Quantum Number : Cs ) - ° describes the spin of an E (clockwise. or anticlockwise) NE Atx Mex o spin angular momentum = ¥+1 # Energy of orbitals : - Mono electronic ' species Multi electronic species There is nuclear attractive force is nuclear attractive force only It well ° 0 as as inter electronic forces. oops Tip. :.tn of all orbitals in of different orbitals is different Energy shell Energy ° same o is same in same shell due to inter electronic repulsion. Energy only depends principal Energy depends upon n' well ' ° on o as as Quantum number ' '. d. 1st ( 3s s Us < 3d 25 2ps 3ps Iss Is ⇐ 2ps 3s=3p=3d # Zeff ( effective Nuclear charge ) : -. ↳ Due to inner shell -0 by -0 shielding of outer shell e from nucleus e , net ④ ve charge experienced by outer shell e-0 from nucleus. Zettle lT Shielding Power s > p > d >f Foo same sub shell Energy t as atomic no. Kett ) : fzs 1H ) 7 Ezs ( Li ) 7 Eas (Na) > Ez ( k) ef , here n→ const , ding Y ' meanings Ex - za TM Aufbau Principal s. 29 Et o Acc to Aufbau principal , e -0 are filled in orbitals in increasing order of energy. ° Lst e -0 are filled in lower energy orbitals and then e-0 are filled in higher energy orbitals. Energy : - Lss 2sc2pC3s 7-s C 3ps Us a 3d < 4ps 5s cads 5ps 655 4fC5d < 6ps Pauli exclusion Principle 6 It States that no two e-0 can have same quantum number ⑧ Two. can be filled in orbitals but they must have Opp -0 e spin.. Magnetic moment or Paramagnetism : - µ = 14¥ ⇐ total spin = 42 µ 1¥ n → no of unpaired of - -. SI Unit → B. m. (Boho magneton) 1dB substance having unpaired Paramagnetic -0 → e Diamagnetic substance s no unpaired -0 e In - - o) Hund 's Maxm Multiplicity Rule ↳ Pairing of e-0 in orbitals of same subs hell does not take until each orbital subs hell is place that of singly occupied or half filled. Electronic configuration of Atoms ↳ Distribution of electrons into orbitals of an atom is called its electronic configuration. Two ways to assign electronic configuration of different atoms : - CB sapbd ' - - - notation : In it , the letter symbol shows subshell and the superscript such as agb , c , ete , shows the number of - - - electrons present in the subs hell. IB Orbital diagram : In this , box is used represent each orbital of to the subs hell and an arrow [ with positive (9) or negative H ) spins) represents the electron I Is ill I. ego.. d LI: write E c of :( - -. is My ↳ = ↳2 25 2ps 352 ID At = 15 252 2ps 35 3ps Iii ↳ Me = 152 252 2ps Qb zoca = Ls' 25 2ps 352 3ps 452 4479 273M ( etgfnfumlf.fi#In5LvBzgNP--Ls22s22p63s23p6 d CAN,s4s23d4X. X 248 = → CAB s4sd3d5 , 453 d FAI , Ys23d8 ' ⑧ * " aid FAI 4523019 X [Arbus 3d ' zgcu → = , K3B for Ions → lower energy tf tf yet AIET IGHT → for cation for anion - last # A- Heft G- ate = CAN ,s4s23d6 80=42252,04 ✓\ G 's ( go -2=15252136 fe -12 feT3 CAN ,g3d6Ys° ( A%3d54s° Node and Nodal planes ↳ The region where the probability of finding an electron is minimum or nearly zero is called as node.. Radial Node : spherical region where probability of finding @ is zero. formula : (n - d- L) Angular Node : plane where probability of finding is zero. formula : Il) Radial node n l I =L o L Is → - = - - - ey → Angular node = l O - Radial = nd I - =3 - o - L 2 zg \ l Angular o =