Atomic Structure Questions and Answers

The correct Schrodinger s wave equation for a electron with total energy E and potential energy V is given by 1 Py 20 x y z 2 Pu 20 x y 3 24 z 877 mh 87m h 24 26 2 4 8x y2 z 4 None of the above E V 0 E V 0 87 m E V 0 h

ect the statement that was not part of Dalton s atomic theory In the atom negatively charged electrons are suspended in a sphere of positive charge b Matter consists of tiny indivisible particles called atoms c Each atom of a particular element has the same mass but atoms of different elements have different masses d Atoms combine in small whole number ratios to form molecules e Atoms of some pairs of elements can combine with each other in different whole number ratios to form different compounds

Which of the following energy change is less than third Balmer transition in He ion 1 First excitation energy of He ion 2 Third separation energy of Li ion 3 Fourth excitation energy of hydrogen atom

128 The first orbital of H is represented by 3 2 4 1 T probability of finding the electron at a distance r from the nucleus in the region dV is a y dr u 4tr dr V y riao where ao is Bohr s radius The 27 2 e 9 2 b y 4 r dv d Sydv

17 The frequency of first line of Balmer series in hydrogen atom is vo The frequency of corresponding line emitted by singly ionised helium atom is a 2v0 b 4 vo d vo 4 c vo 2 When atoms are bombarded with a particles only a fe

4 All of these are correct 65 The wave number of electromagnetic radiation emitted during the transition of electron in between two levels of Li ion whose principal quantum numbers sum is 4 and difference is 2 is 1 R 2 4R 3 8R 8 4 R

Emission transitions in the Paschen series end at orbit n 3 and start from orbit n and can be represented as v 3 29 x 1015 Hz 1 32 1 n Calculate the value of n if the transition is observed at 1285 nm 1 6 2 5 3 8 4 9

on energy of Het is 19 6 x 10 18 J per atom 45 af Het then the energy of Be ion in the second stationary state is 19 610 18 J per atom IUPAC Naming Atomic Structure Periodic a fer en 1 4 9 x 10 18 J 2 44 1 x 10 18 3 11 025 x 10 18 J 4 None of these 1 4 9 x 10 18 J 2 44 1 x 10 18 3 11 025 x 10 18 J 4 E

3 6 34 x 10 4 1 49 10 51 Pick out the correct order of magnetic moment among the following 1 Na Cr2 Co Fe 2 Na Co2 Fe Cr2 3 Nat Co Cr Fe 4 Na Fe Cr2 Co tround 67

If m and e are the mass and charge of the revolving electron in the orbit of radius r for hydrogen atom the total energy of the revolving electron will be Online 2014 SET 3 a c me r 1 e r b d e r 1 e

benzene 50 At 200 C hydrogen molecule have velocity torr in 2 4 x 105 cm s The de Broglie wavelength in this case is approximately a vapour 1 1 2 1000 A

c 100 106 Of the following transitions in hydrogen atom the one which gives an absorption line of lowest frequency is b n 3 ton 8 a n 1 to n 2 d n 8 to n 3 c n 2 to n 1 ording to Bohr s model of the hydrogen atom the haracterised by the principa

The emission spectra of atoms in the gaseous phase do not show a continuous spread of wavelength from red to violet rather they emit light only at specific wavelengths wit dark spaces between them Such spectra is are called Silla Choose only 1 answer B C line spectra atomic spectra both A and B

CAREER INS 81 The correct set of four quantum numbers for the last elec 81 37 tron of Rubidium atom Z 37 is 1 5 2 5 3 5 4 4 0 1 1 1 0 0 1 1 S 1 2 1 2 1 2 1 2 n 1 5 2 5 3 5 4 4 1 0 1 1 E o o 0 1 S 1 2 1 2 1 2

1 The time period of revolution in the third orbit of Li ion is x second The time period of revolution in the second orbit of He ion should be 8 4 XS 27 An element of atomic weight Z consists of two 1 xs XS 3

1987 8 7 0 A bulb emits light of wavelength nm The bulb is rated as 200 W and 14 of the energy is emitted as light How many photons are emitted by the bulb per second 1 1 2 x 1021 3 1 33 x 10 1 2 4 x 10 0 4 4 x 1019

Which of the following expressions represents the spectrum of Balmer series If n is the principal quantum number of higher energy level in Hydrogen atom R n 1 n 1 1 V 2 V 3 V 4 V R n 2 n 2 4n R n 2 n 2 n R n 1 n 1 4n cm cm cm cm 1 1 1

id 10 1 h k 0 Important Formulas of Bohr s Theory and hydrogenic ions That is ions having one elecron for example Their Application in Numerical All the formulas of Bohr s theory are applicable to hydrogen or H Li and Be For example He Li and Be e a E S No Aton b Comparison formula for numericals IE PE KE Radius of nth shell 2x me n h Velocity of nth shell IEH like atom Radius of Bohr s orbit No of waves made by e in nth shell IE and TE No of revolutions made by nth shell KE and TE Term 2 Angular momentum in orbit Number of waves in nth orbit v 6 5 10 5 x r 0 529x A Bohr s radius is ro when n 1 2 1 V x2 185 10 11 IE E E IE 0 E E IE like stown Ze 2r KE P E T 1 5x10 16x myr Ze TE xz Ze 2r nh 2 r Value of n At infinity E 0 as E i e at infinity electron is no longer a part of atom d Comparison of energy levels in terms of energy difference and radius difference 1 E E E E E E E E ii r F r F 1 rs 1 Formula KE Ze 2r TE 2r Ze 2 2 cm s S X 1 Branz 11 V Z Inference Tx IE E LEH O 13 6x z n xz 2 22 V Zm V M Z 27 2x 2 11 2 eV atom eV atom TE 13 6x eV atom h 2n h If n 2 mvr If n 1 mvr T

Zero Marks 0 In all other cases The uncertainty in the position of an electron is equal to its de Broglie wavelength Find minimum percentage error in measurement of its velocity under this circumstance Consider the following first order decomposition reaction

4 Total number of electrons 3 1 2 Ti 5 If Zef of F Z 9 is X and Zef of Li Z 3 is Y then find the 36 f F Z 9 Z 4 240 1 70 3 00 value of IX YI eff 15 25 2P5 1525 6X08512X0 35 270 8 1 4 90 3 90 3 2 90 4 1 90 6X0 35 2X SED 1 70 1 4 90 2 3 90 3 2 90 4 1 90 103 3 Ya IX YI eff 3 0 6X0 35 2X0 85 2x0 3 2 10 0 2 1 70 3 10

The de Broglie wavelength of electron of He ion is 3 329 If the photon emitted upon de excitation of this He ion is made to hit H atom in its ground state so as to liberate electron from it what will be the de Broglie s wavelength of photoelectron 1 0 1518 2 6 1518 3 2 3518 4 4 1218

32 Write the period number group number and block of the 32 42 41414 High tea and and fac sad zien ari zi IUPAC Naming Atomic Structure Periodic Tab element having atomic number 42 37 38 39 40 41 42 8 1 5 5 d 2 5 6 d 3 5 2 d 4 5 15 p Choose 3282 1 5 5 d 2 5 6 d 3 5 2 d 4 5 15 p

Select the correct statements A Over a boundary surface value of probability density lyf is constant for a orbital B Probability of finding an electron is 100 in an orbital C Number of angular nodes are n 1 1 D For 1s orbital the probality density is maximum at the nucleus

From the following observations predict the type of orbital Observation 1 x y plane acts as nodal plane Observation only Observation 3 R r v s r curve obtained for the orbital is R r 2 The angular function of the orbital intersects the three axis at origin

The measurement of the electron position is associated with an uncertainty in momentum which is equal to 1 10 18 g cm s g cm s The uncertainty in electron velocity is mass of an electron is 9 x 10 28 g CBSE PMT 2008 a 1 106 cms 1 1 10 cms 1 1 b 1 105 cms do 8 1 1 10 cms 1 1 d momentum are equal the

4 0 0 Four diatomic species are listed below in different 58 HP T sequences Which of these presents the correct order of their increasing bond order ant 15 19 C H NO 0 2 He 0 NO C 0 NO C H 4 No C 0 He V 1 C2 He NO 0 2 He 0 NO C 3 0 NO C2 He 4 NO C2 O He

A photon of 300 nm is absorbed by a gas and 69 then re emits two photons One re emitted photon has wavelength 496 nm the wavelength of second re emitted photon is U759 nm 2 857 nm 4 657 nm 3 957 nm

75 Energy levels A B C of a certain atom corresponds to 75 increasing values of energy i e EA E E If and A are the wavelengths of radiations corresponding to the transitions C to B B to A and C to A respectively which of the following statement is correct to B 14 2 42 n 0 n 1 n 2 43 2A1 1 2 3 2 2 0 C B A2 A3 2 23 A 73 2 2 2 23 2 2 4 2 773

3 1 x 100 cm s 4 1 x 105 cm 5 1 7 1 12 In carius method 0 05 gram organic compound gave 0 03 12 Rafafu 0 05 in fe 0 03 TH AgCl gram AgCl The percentage of chlorine in the compound 3 1 x 106 cm 5 will be 4 1 x 105 cm s 1 14 84 axlo 2 18 2 XIV 20 3 27 7 F 105 35 5 7 03 4 64 2 If the radius of ions such as Mg2 Cst 02 S and Cr 13 f3 for Mg Cst F 435 2 18 2 5x29400 3 27 7 4 64 2 Excel 1485 R 1396 52x88 14 84 108 35 93 03 X108 5 crat far

Question 16 Among the second period elements the actual ionization enthalpies are in the order Li B Be C o KI F Ne Explain why i Be has higher A H than B ii O has lower AiH than N and F

Aqueous solution of two compound M O H M O H are prepared in two different beakers If EN of M 3 4 M 1 2 0 3 5 H 2 1 Then nature of solution will be respectively A B Acidic Basic Acidic Acidic Basic Acidic

Which of the following options does not represent ground state electronic configuration of an atom a 1s 2s 2p 3s 3p6 3d8 4s 3s 3p6 3d 4s b 1s 2s 2p 6 c 1s 2s 2p 3s 3p6 3d 0 4s 345 6 345 11 d 16 26 206 3 306

2 I II e III rect 4 None of these 4 T The distance between third and 2nd Bohr s orbit of hydrogen 64 Si fa face au dau ar 1 0 529 x 108 cm 22 646 108 cm 3 2 116 x 108 cm 4 1 058 x 108 cm The ratio of radi n 83 82 5 x 9 81 h 6 625 0 Jubs o 2 645 1 0 529 x 10 8 cm 2 2 646 x 108 cm 3 2 116 x 108 cm 4 1 058 x 108 cm

Number of spectral line obtained when electron is provided with a photon of energy of 11 eV for H atom 01 02 00 06

2 1 25h 1 X 4 TL 58 If ionisation energy for He ion is x Kcal mol then find out 58 Het x Kcal molt the energy of electron in 3rd Bohr orbit of Li ion in terms of x in Kcal mol X 2 4 13 4x JA 4x If x E Fixzz2 erroct 4 E x 2 T Kcal mol x 1 X x X 2 4 32 3 4x 4 4x ccording to 59 THIS BAR H 5

108 cm 4 1 058 x 108 cm 65 The ratio of radius 2nd 4th and 6th orbits of hydrogen 65 A 2nd 4th en 6th 3 0 529 9 4 1 2 4 6 21 4 9 3 1 4 6 4 1 2 3 5 The energy of electron in excited tom in 0 52915 2 645 98 91 h bh 1 XY CC 2 2 646 x 108 cm 3 2 116 x 10 8 cm 1 2 4 6 2 1 4 9 3 1 4 6 4 1 2 3 f 6 13 6 43 d tis 34 eV a

INSTITUTE 79 Angular momentum of electron for hydrogen in second orbit 79 El 24 at se en la tiam ante durant is x then it will be for Li 2 in Ist excited state Class XI Marcel Batch Atomic Structure A B C 1 3x 2 9x 1 3x 2 9x 3 x 2 XX 3 x 2 80 If the kinetic energy of a particle is double 1 2 N EV

81 SCQ If the ionic potential of ions is in the order M M Mand b polarizability of ions is in the order x y z Select the combination of ions having more covalent character as compared to My b A B en Max Mez Correct Answer

The effective nuclear charge experienced by a valence electron in an atom will be less than the actual charge on the nucleus because of the shielding or screening of valence electron from the nuclecus by intervening core electrons

2 4 4 1 3 29 Calculate the energy of a photon of sodium light of wave 69 44 folucnt 1368 length 5 862 x 10 6 m in Joules 4 1 3 mX10 17177 105 1441 1 3 35 x 108 J 2 3 38 x 10 10 J 3 3 38 x 10 12 J y 4 2 38 x 10 16 J 20 14 41 1360 1362 2000 4 1368 42 5 862 x 10 16 1 3 35 x 10 8 J 2 3 38 x 10 1 J 3 3 38 x 10 12 J 4 2 38 x 10 16 J Y 1800 6 82 10 37 8 662 X10 6620 62

46 The quantum numbers of four electrons are as follows 1 Electron 1 ii Electron 2 1 Electron 3 n 3 3 4 1 0 0 m 2 1 0 0 5 1 222 1 2 1 2 iv Electron 4 3 1 2 2 The correct order of decreasing energies of these electrons is 1 Electron 2 Electron 1 Electron 3 Electron 4 2 Electron 4 Electron 3 Electron 1 Electron 2 3 Electron 4 Electron 3 Electron 2 Electron 1 4 Electron 1 Electron 2 Electron 4 Electron 3 47 If the radius of first orbit of H atom is a then de Broglic Class XIII Spartan Batch Chemical Arithmetic Atomic Structure Solid State 46 1 Electron 1 ii Electron 2 iii Electron 3 iv Electron 4 n 3 3 4 3 1 0 0 2 m 1 0 0 2 5 12 12 1 2 1 2 1 Electron 2 Electron 1 Electron 3 Electron 4 2 Electron 4 Electron 3 Electron 1 Electron 2 3 Electron 4 Electron 3 Electron 2 Electron 1 4 Electron 1 Electron 2 Electron 4 Electron 3

the degenerate orbitals When several electrons occupy a set of degenerate orbitals the lowest energy state corresponds to the maximum possible extent of single occupation of orbital and parallel spins Hunds rule The loss of exchange energy increases the stability As the stability more difficult There is no loss of omes

4 All 4 47 When an electron moving with a speed of 600 ms 1 with 47 600 ms n qu gu us d gia xfafradal an uncertanity of 0 005 then calculate the uncertainity in 0 005 azia n feefa fred og position of electron 1 1 4 x 10 3 m 2 1 9 10 3 m 3 2 9 x 10 3 m 4 3 9 x 10 3 m Teoman effect explains splitting of spectral lines in 1 1 4 x 103 m 2 1 9 x 103 m 600 X 0 005 X 9 1 X 4 X 3 4 3 2 9 x 10 m 4 3 9 x 103 m fatt 6 627 10 DXX DV 220 6 1 103 662x10 34 Dx DP DAT 0x skom h An

Heat treatment of muscular pain involves radiation of wavelength of about 900 nm Which spectral line of H atom is suitable for this purpose R 1 x 105 cm h 6 6 x 10 34 Js c 3 108 ms JEE Main 2019 1 Balmer 2 3 Paschen 5 2 Lyman 1 4 Paschen 23

Which one of the following statements related to lanthanons is incorrect 1 Europium shows 2 oxidation state 2 The basicity decreases as the ionic radius decreases from pr to Lu 3 all the lanthanons are much more reactive than aluminium 4 Ce 4 solution are widely used as oxidizing agent in volumetric analysis

The de Broglie wavelength 2 associated with a photoelectron varies with the frequency v of the incident radiation as vo is threshold frequency JEE Main 2019 1 v vo 1 x 3 x 1 v v 2 1 2 x 4 x 1 1 v vo 4 1 v v 3

The graph between y2 and r radial distance is shown below This represents JEE Main 2019 lyf 1 1s orbital 3 2p orbital 2 2s orbital 4 3s orbital

3 Four species are listed below i HCO3 iii HSO4 ii H30 iv HSO3F Which one of the following is the correct sequence of the acid strength 1 iv ii iii i 3 i iii ii iv 2 ii iii i iv 4 iii i iv ii

What contribution did John Dalton make to atomic theory A B C D he discovered that every atom was positively charged he discovered that every every element consisted of one type of atom he discovered that atom had nuclei he discovered that atoms could be divided into smaller parts

An element with mass number 95 have 4 unit positive charge and 25 more neutrons than electrons in the given ionic state Its atomic number is Z then find the value of Z 10