Atomic Structure Questions and Answers

below ace 3 The minimum 36 A ray of light propagates from glass refractive me placed over the to cut off all light index 3 2 to water refractive index 4 3 The value of the critical angle 4 3 m GO0029 lium of refractive n 1 sin 1 2 3 sin 8 9 2 sin 55 4 sin 5 7

focal length REFRACTION AT PLANE SURFACE SNELL S LAWS TIR 4 30 cm GO0018 25 The colour are characterised by which of following character of light bject and its 4 Zero 1 Frequency 3 Wavelength 2 Amplitude 4 Velocity G00025

0 Choose the correct statement 1 6d orbital has 4 radial nodes 2 The energy of 7d is higher than energy of 7s in case of hydrogen atom 3 72 orbital does not have 2 nodal plane 4 Energy sequence of the following orbitals is 3s 3p 3d 4s for an element having Z 20

incorrect statement among the following is Particle nature of electromagnetic O radiation is manifested in photoelectric effect O The number of electrons ejected in photoelectric effect is proportional to the intensity of light used O Spectral lines in Lyman series falls in visible region Energy levels in hydrogen atom is

If a particle of mass 0 5 g is moving with a velocity of 200 m s then the wavelength associated with the particle is h 6 625 10 34 Js 6 625 10 32 m 6 625 10 33 m 6 625 10 34 m

In an excited sample of Li 2 ions with all the electrons in the same energy state n produces 3 different spectral lines when all of them are now found to be in 1st excited state What can t be the orbital angular momentum of the electron present in state n O sqrt 12 h O sqrt 2 h 0 O sqrt 20 h

CHEMISTRY IA 58 In a H atom the transition takes place from L to K shell If R 1 08 x 107m the wave length of the light emitted is nearly 1 4400A 2 1250A 3 1650A 4 1850A 9 The wave length of first member of Balme hydrogen atom is nearly TH

1 H 2 2740 Hz 3 2350 Hz 4 1685 Hz 32 The string of a violin has a frequency of 440 cpr If the violin string is shortend by one fifth it frequency will be changed to 1 440 cps 2 880 cps 3 550 cps 4 2200 cps

6 6 5 KJ 56 Under the same conditions how many mL of 1M KOH and 0 5 M H SO4 solutions respectively when mixed for a total volume of 100 mL produce the highest rise in temperature a 67 33 c 40 60 b 33 67 d 50 50

1 6 Which of the following quantum numbers for orbitals in hydrogen atom has a greater energ for electrons i n 3 1 2 and m 1 ii n 3 1 2 and m 1 the nucleus 2

1 When a certain metal was irradiated with a light of frequency 3 2 x 10 6 the photoelectrons had twice the kinetic energy as emitted when the same metal was irradiated with light of frequency 2 0 x10 6 Hz Calculate the threshold frequency of the metal

52 Based on equatio E 2 178 x 10 18 J Z 2 n certain con clusions are written Which of them is not correct a The negative sign in equation simply means that the energy of electron bound to the nucleus is lower than it would be if the electrons were at the infinite distance from the nucleus b Larger the value of n the larger is the orbit radius

52 Based on equati E 2 178 10 18 J 2 Z n certain con clusions are written Which of them is not correct a The negative sign in equation simply means that the energy of electron bound to the nucleus is lower than it would be if the electrons were at the infinite distance from the nucleus b Larger the value of n the larger is the orbit radius c Equation can be used to calculate the change in energy when the electron changes orbit d For n 1 the electron has a more negative energy than it does for n 6 which means that the electron is more loosely bound in the smallest allowed orbit

Question Number 121 Question Id 8135612201 Question Type MCQ Display Question Number Yes Is Question Mandatory No Single Line Question Option No Option Orientation Vertical Calculate the frequency of the violet light given 400 nm on 500 aus Jesso nowod 400 nm rasgwasa Options 1 2 3 7 5 x 10 4 Hz 4 5 x 10 4 Hz Yes 4 5 x 10 10 Hz 7 5 x 10 10 Hz

Which of the following electronic transitions in hydrogen atom will require the largest amount o energy 1 From n to n 1 2 From n 1 to n 2 3 From n 2 to n 5

Question Number 136 Question Id 8135612216 Question Type MCQ Display Questi Number Yes Is Question Mandatory No Single Line Question Option No Option Orientation Vertical An element has electronic configuration 2 8 10 2 The total number of electrons in each subshell is given as from the complete electronic configuration assures des jo 2 8 10 2 mr God and sexy and dese Day 28 Deg Dates Options 1 s 6 p 12 d 4 f 0 2 S 8 p 10 d 2 f 2 3 S 8 p 12 d 2 f 0 4 S 6 p 12 d 2 f 2

Identify the one electron species that exhibits the spectrum above i e give the symbol for the element and the charge on the species OH Het O Be3 N6 O 15 B A 30 4 wavelength nm

statement is 23 565 Box Jeg Je auj a Ke Jeuk spowo Sopgev dod rc D5OED Options 1 www android universityupdates in www universityupdates in www ios universityupdates in www android previousquestionpapers com www previousquestionpapers com www tos previousquestionpapers Heisenberg s uncertainty principle 35 unges Down Particle wave dualism of de Broglie

1 Question Number 121 Question Id 7512365241 Question Type MCQ Option Shuffling Yes Display Question Number Yes Single Line Question Option No Option Orientation Vertical HH5 555 13 6 eV He He jobs eV os Options 2 3 The amount of energy required for the conversion of H to H is 13 6 eV The amount of energy in eV required for the conversion of He to Het is 27 2 40 8 54 4 01

Highest energy molecular orbital occupied in case 1 of N is 5 2 620 3 px ONLY V 2 2p 4 2py u

Consider the following statements S All group 2 elements are known as alkaline earth metals S Radium salts are used in radiotherapy S3 Hydrated halides of Ca undergo dehydration on heating whereas the corresponding halides of Mg on heating suffer hydrolysis S4 The solubility of alkaline earth metal hydroxides increases down the group in water If x and y are the number of statement s is are correct and incorrect respectively then the value of x y is

What should be the frequency of radiation to produce photoelectron having half the kinetic energy of those produced by the radiation of frequency 10 8 sec The critical frequency for emitted photoelectrons from a metal surface is 8 x 1016 sec A 12 x 10 4 sec 1 B 46 x 10 4 sec c 8 x 10 4 sec A 1014 1 1

Hydrogen molecule exist in two nuclear spin isomeric forms Which of the following is not true regarding the two isomers They have different resultant nuclear spin They have identical chemical properties They have different physical properties The internal energy of the ortho H is lower than that of para H

Calculate the energy in joules required to shift the electron of the hydrogen atom from the first Bohr orbit to the fifth Bohr orbit Also find the wavelength of the light emitted when the electron returns to the ground state 3 The ground state electron energy 2 18 x 10 18 J atom h 6 626 x 10 34 Js

In the measurement of the quantum efficiency of photosynthesis in green plants it was found that 8 quanta of red light at 6850 were needed to release one molecule of O The average energy storage in the photosynthesis process is 112 kcal mol of O released What is the energy conversion efficiency in the photosynthetic process

c 152 pm 35 A compound MpXq has cubic close packing ccp arrangement of X Its unit cell structure is shown in figure The empirical formula of the compound is a MX c M X O O O M O X O b MX 2 d M5X14

A non stoichiometric compound of Fe has a formula Feo 930 Percentage fraction of Fe present as Fe2 and Fe3 ions respectively are 80 20 15 85 85 15 90 10

a Discuss some general limitations of the Beer Lambert law 1 mar 5 Calculate the number of photons having a wavelength of 10 0 um required to produ 1 0 kJ of energy 11 marl

Consider a sample of sulfur atoms prepared in the absence of an external magnetic field What is the average value L in multiples of h of the z component of the angular momentum for one of the outer 3p electrons in the sample

1 Consider the following six electronic configurations remaining inner orbitals are completely filled 3s 3p 3s MAN I III IV V 3s 4s 4s 4s 3p II 3d TAINAL nnnnn 4p nim 3d 11 VI Mark the correct option a Stability order V I IV III b Order of spin multiplicity IV III I II c V does not violate all rules of electronic configuration d If VI represents A and when A kept near a

quency of photons emitted in Paschen series is given by v 3 29 x 10 5 hz 1 1 3 2 n Value of n for photon having wavelength 1285 nm will be 1 n 3 2 n 4 3 n 5 4 n 6

18 The wave number of a given spectral like in the atomic spectrum of a hydrogen like species increases 9 4 times when deuterium nucleus is introduced into its nucleus then which of the following will be the hydrogen like species A Li 2 C Het B Lit D Bet3 3

96 What is the frequency of revolution of electro present in 2nd Bohr s orbit of H atom 1 1 016 10 6 S 3 1 626 x 10 5 S 1 2 4 065 10 6 4 8 2 x 10 4 S 1 S 1

7 Arrange the following wavelengths 2 of giver emission lines of H atoms in increasing orde a n 3 n 1 b n 12n 10 c n 5 n 3 Choose the correct option 1 24 3 2 3 2 3 2 2 d n 22n 20 2 2 24 3 4 2

If the ionization energy of hydrogen is 313 8 kcal per mol then the energy of the electron in 2nd excited state will be 1 113 2 kcal mol 3 313 8 kcal mol 2 78 45 kcal mol 4 35 kcal mol A50045

The kinetic energy of an electron in H like atom is 6 04 eV Find the area of the third Bohr orbit to which this electron belongs and the atom A 5 6 x 10 16 cm Be B 17 8 x 10 6 cm He C 8 9x10 6 cm Li D 11 2 x 10 6 cm B

3 B C O N increasing first ionization enthalpy 4 CO SiO SnO PbO increasing oxidising power 2 In context with the transition elements which of the following statement is incorrect 1 In the highest oxidation states the transition metals show basic character and form cationic complexes 2 In the highest oxidation states of he first five transition element Sc to Mn all the 4s and 3d electrons are used for bonding 3 Once the d configuration is exceeded the tendency to involve all the 3d electrons in bonding decreases 4 In addition to the normal oxidation states the zero oxidation state is also shown by these elements in complex 3 Knowing that the chemistry of lanthanoids Ln is dominated by its 3 oxidation state which of the

The de Broglie wavelength A associated with a photoelectron varies with the frequency v of the incident radiation as vis threshold frequency A B C D 1 v v 1 v vo 1 v v Vo 1

lonisation energy of He is 19 6 x 10 18 stationary state n 1 2 Li J atom 1 The energy of the first is A 4 41 x 10 17 Jatomi 1 B 4 41 10 17 Jatomi 1 C 2 2 x 10 15 Jatom 1 D 8 82 10 17 X J atom 1

lonization energy of He is 19 6 x 10 18 tom 1 A stationary state n 1 of Li is 8 82 x 10 17 Jatom 1 B J atom C The energy of the first 4 41 x 10 16 J atom 1 4 41 x 10 17 J atom 1 D 2 2 x 10 15 J atom tom 1

Which of the following is true about the energy of an electron Total energy of electron decreases as we move away from the nucleus Potential energy of electron decreases as we move away from the nucleus Magnitude of kinetic energy of electron is greater than that of potential energ Kinetic energy of electron decreases as we move away from the nucleus

58 Energy required to remove an e from M shell of H atom is 1 51 eV then energy of first excited state will be 1 151 eV 3 3 4 eV 2 1 51 eV 4 13 6 eV

The velocity of electron in a certain Bohr s orbit of H atoms bears the ratio 1 275 to the velocity of light What is the approximately number of orbit closet integer

Conclusions made from energy expression observations are as follows 1 As we go away from nucleus energy of shell goes on increasing this means energy of electron present in that shell goes on increasing Increase in energy means force of attraction goes on decreasing ii iii At infinity E is zero this means there is no force of attraction between electron and nucleus c Electron revolves only in those orbits whose angular momentum mvr is an integral multiple of the factor 2 where his Planck s constant h 2n myr n where m is the mass of the electron v the velocity of the electron n the number of orbit in which electron revolves that is n 1 2 3 and r the radius of the orbit d As long as the electron occupies a definite energy level it does not radiate out energy that is it does not lose or gain energy Excited State of Electron As long as e is in particular state It neither loses energy nor gains energy of its own If an e wants to go from lower to higher state it will have to absorb energy equal to the difference in the energy of two shells On absorbing energy electron goes to the excited state So electrons present in the ground state are called absorbers and those that emit energies are called emitters e present in ground state can only behave as absorber Nucleus a Energy absorbed E E Note This a differenc Concept Concep 11 n Note To Formi Note i IE of MATHE POSTU Calcu

Column I column II contain data on Schrondinger Wave Mechanical model where symbols have their usual meanings Match the columns Column I A 41 A B Y 4 Column II Type of orbital 1 P 4s m C Y q f K independent of angular function R 3s D Atleast one angular node is present Ans A P B P Q S C P R D Q S Q 5px S 6d xy m

A monoelectronic species in energy level with energy X was provided with excess of energy so that it jumps to higher energy level with energy Y If it can emit six wavelengths originated from all possible transition between these group levels then which of the following relation is correct n is the principal quantum number of energy level X A B C X 1 n Y 6 3 J W n X n 1

Problem 43 Calculate the average volume available to a molecule in a sample of N at NTP Also report the average distance between two neighbouring molecules if a nitrogen molecule is assumed to be spherical Commen on the result if the radius of one N molecule 2 x 10 8 cm

6 The first Lyman transition in the hydrogen spectrum has AE 10 2 eV The same energy change is observed in the second Balmer transition of 1 Li 2 Lit Het 4 Be

changes 4 In flame most of the lines emitted are from the a neutral atom b gaseous atom c gaseous ion d ion 5 Spectral interference is caused especially when are used to isolate the desired radiant energy

Units of parts per million ppm or parts per billion ppb are often used to describe the concentrations of solutes in very dilute solutions The units are defined as the number of grams of solute per million or per billion grams of solvent Bay of Bengal has 2 48 ppm of lithium ions The molality of Lit in this water is atomic number of Li 7 A 1 5 x 104 m B 1 7 x 10 4 m C 3 5 x 10 4 m