Atomic Structure Questions and Answers

Given Rydberg constant R 105 cm Supposing if electron jumps from M shell to K shell of H atom the frequency of the radiation emitted in cycle s would be 8 1 105 8 3 10 1 2 4 8 13 8 9 1015 1015

PC H O CH 3PO4 5HCI 4 CH OH CH CO O CHOCOCH CH3COOH 62 In the following free radical substitution reaction hv CH CH CH CH3 Br 1 R is formed 2 S is formed 3 both R and S are formed 4 none of the above is formed 3 CH CH CH HI A 2 C6Hr Aq KOH B 62 3 3C H5OH PCI H O CH PO4 SHCI 4 C H5OH CH CO 0 C H OCOCH CH COOH fe CH3CH CH CH3 Br 1 R32 Fafta m 2 Safaftia 3 Rasa fatta am 4 3 STE no fuf hv 34 e 63 CH CH CH HI A Aq KOH 67

Which of the following is are not a favorable condition s for the formation of a ionic bond i Low ionization potential for the easy formation of cation ii High electron affinity for the easy formation of anion iii Large electronegativity difference between two elements forming an ionic bond iv High ionization potential for the easy formation of cation A i and ii B i ii and iii c ii only D iv only

1 Vapor pressure equation for liquid zinc is given by the following expression 6676 log p mmHg 1 7210gT 12 448 T The triple point temperature for zinc is 419 C and the pressure at this temperature is 0 0082 atm The melting temperature of zinc is 420 C and enthalpy of melting of zinc is 1740 cal mole degree a A piece of zinc placed inside a ceramic crucible is heated in an evacuated chamber to elevated temperatures in order to generate a zinc vapor pressure of 0 2 atm inside the chamber To what temperature zinc should be heated to get this atmosphere b What would be the vapor pressure of zinc inside the chamber when zinc was

Which of the following will violates Aufbau principle as well as Pauli s exclusion principle 1 2 3 2p 2 N O 2p m o H

ne figure that is not a direct manifestation of the quantum nature of atoms is JEE Main 2020 Increasing wavelength 1 2 3 Absorption spectrum Internal energy of Ar 300 400 500 600 Temperature K Intensity of black body radiation T T T 1 Wavelength

The spectrum of hydrogen molecule 18 Calculate de Broglie wavelength of a neutron mass m 1 6x10 27 kg moving with kinetic energy of 0 04 eV 1 146 A 3 1460 A Consider the following 19 2 14 6 4 1 46

4 A certain radiostation broadcasts at a frequency of 900 KHz The wavelength of electromegnetic radiations broadcast by radiostation is 1 900 m 3 2 70 km 2 270 m 4 330 m

4 The energy corresponding to second line of Balmer series for hydrogen atom will be 1 12 1 eV 3 2 55 eV 2 1 89 eV 4 13 6 eV

31 For the Balmer series in the spectrum of H atom 1 1 n n v RH the correct statements amodica 1 M to VI are 1 As wavelength decreases the lines in the series converge II The integer n is equal to 2 III The lines of longest wavelength corresponds to n 3 1 1 II III IV The ionization energy of hydrogen can be calculated from wave number of these lines JEE Main 2020 2 II III IV

0 84 g of a metal carbonate reacts exa ctly with 40 ml of N 2 H2SO4 The equi valent weight of the metal carbonate is Why is the equivalence of metal carboo nate equal to equivalence of H2SO4 An d why is H2SO4 taken as solution and n ot solvent

5 If first ionization ptoential of an atom is 36 V then the second excitation potential will be 1 10 2 V 2 12 V 3 27 V 4 32 V

10 One mole of nitrogen is mixed with 3 mole of hydrogen in a closed 3 litre vessel 20 of nitrogen is converted into NH 3 Then K for the N H NH3 is 3 2 2 NTSE 1994 11 a 0 36 litre mol b 0 46 litre mol c 0 5 litre mol 1 1 1 1 d 0 2 litre mol A characteristic feature of reversible reaction is that

16 Calculate the Gibb s energy change when I mole of NaCl is dissolved in water at 25 C Lattice energy of NaCl 777 8 KJ mol AS for dissolution 0 043 KJ mol and hydration energy of NaC1 774 1 KJ mol 1 9 114 KJ mol 3 5 4 KJ mol 2 11 4 KJ mol 1 4 1 5 KJ mol 1

Which one of the elements with the following outer orbital configurations may exhibit the largest number of oxidation states 1 3d 4s 2 3d5 4s 3 3d5 4s 4 3d 4s

46 Which among the following state symbols are possible for the element X with atomic number 5 A P P and P B P 3 2 and P1 2 C S1 2 and So D P 1 2 P 3 2 and P5 2

A certain electronic transition from an excited state to the ground state of the H atom in one or more steps gives rise to four lines in the visible region of the spectrum how many lines does this transition produce in the infrared region of the spectrum 1 3 3 5 2 4 4 6

The wavelength of the photoelectric threshold of metal is 230 nm Determine the K E of photoelectron ejected from the surface by UV radiation emitted from the second longest wavelength transition downward of an electron in Lyman series of the atomic spectrum of hydrogen R 1 09677 x 107 m 1 0 074 x 10 16 J 2 1 937 x 10 18 J 3 6 213 10 18 J

n and a n 4 1 b n 4 0 c n 3 2 d n 3 1 Can be placed in order of increasing energy as 1 c d b a 2 d b c a 3 b d a c 4 a c b d a n 4 1 c n 3 2 b n 4 0 d n 3 1 1 c d b 3 2 d b c a 3 b d a c 4 a c b d wa wafted fabu

CF4 is a potent greenhouse gas due to IR absorption and inertness in the atmosphere Let s work through some of the associated factors 3 Find the experimental gas phase vibrational spectra for CF4 and CH4 and tabluate the data Provide your references not Google

How does black body radiation explain particle nature of electromagnetic radiation Furthermore how does the EM wave theory fail to explain this phenomenon 7 and arrived at a satisfactory relationship by making an assumption that absorption and emmission of radiation arises from oscillator i e atoms in the wall of black body Their frequency of oscillation is changed by interaction with oscilators of electromagnetic radiation Planck assumed that radiation could be sub divided into discrete chunks of energy He suggested that atoms and molecules could emit or absorb energy only in discrete quantities and not in a continuous manner He gave the name quantum to the smallest quantity of energy that can be emitted or absorbed in the form of electromagnetic radiation The energy E of a quantum of radiation is proportional experim to its frequency v and is expressed by orily on equation 2 6 2 6 Max Pla E hv The proportionality constant h is known as Planck s constant and has the value 6 626x10 34 J s With this theory Planck was able to explain the distribution of intensity in the radiation from black body as a function of frequency or wavelength at different temperatures ed intens in any its its tempera sity of radi he increas um value arts decrea as sh ngth ture increa rt wavelen o predict function Quantisation has been compared to standing on a staircase A person can stand on any step of a staircase but it is not possible for him her to stand in between the two steps The energy can take any one of the values from the following set but cannot take on any values between them E 0 h 2h 3hn nhu Uni Priz Pla the Pho In 1 exp cur exa wel in Ph thi i

160 A Hydrogen ion moving with a velocity of 10 Q 160 3 10 m s 10 4 Tara m s enter perpendicularly in a magnetic field of 10 4 T Then radius of circular path will be a qaror 1 10 01 mm 3 101 mm 2 1 01 mm 4 0 101 mm er at forst 1 10 01 mm 3 101 mm Medic 2 1 01 mm 4 0 101 mm

4 the electron is not in a d orbital 4 Calculate the minimum and maximum number of ele which may have magnetic quantum number m spin quantum number s 1 in chromium Cr 1 0 1 2 1 2 3 4 6

or stability due higher than that of O Further the effect of increased nuclear charge outweights the to exactly half filled orbitals therefore the A H of N and O are lower than that of F 3 17 How would you explain the fact that the first ionization enthalpy of sodium is lower than that of magnesium but its second ionization enthalpy is higher than that of magnesium Ans The F C of Na is 1 5 25 2n6 35 and E C of Me is 1s 25 2p6 352 In both the cases first electron is to

om the e of the 88 ALLEN A communication satellite of earth which takes 24 hrs to complete one circular orbit eventually has to be replaced by another satellite of double mass If the new satellites also has an orbital time period of 24 hrs then what is the ratio of the radius of the new orbit to the original orbit

1 m me and r 3 mg only GR0086 87 Near the earth s surface time period of a satellite is 1 4 hrs Find its time period if it is at the distance 4R from the centre of earth 1 32 hrs 2 8 2 3 8 2 hrs 4 16 hrs 2 m Re and r 4 mg and r hrs GR0087 93 distance time per 1 4 2 3 4 yea A satellit radius R E is 1 3 GM GM

In hydrogen atom spectra if the ratio of wavelengths corresponding to the first of Lyman series and the first line of Balmer series is 9 a the value of a is Options 1 2 0 5 4 0 8 3 0 6 0 4

ALLEN PLANETARY MOTION WEIGHTLESSNESS 55 Binding energy of moon and earth is GM M GM M 2rum Tam 1 GM M 2 CM M 60

The masses of photons corresponding to the first lines of the Lymann and the Balmer series of the atomic spectrum of hydrogen are in the ratio of 1 5 27 2 1 4 3 27 5 4 4 1

In Y D S E the fringe width is 0 2 mm If wavelength of light is increase by 10 and separation between the slits is increased by 10 then fringe width will be 1 0 20 mm 3 0 401 mm 2 0 165 mm 4 0 242 mm DEWYORLARN

Shape and orientation respectively of an orbital are given by 1 Azimuthal quantum number and magnetic quantum number 2 Magnetic quantum number and principal quantum number 3 Principal quantum number and spin quantum number 4 Magnetic quantum number and azimuthal quantum number

A 100 pure sample of a divalent metal carbonate weighing 2 g on complete thermal decomposition releases 448 cc of carbon dioxide at STP The equivalent mass of the metal is a 40 c 28 SC b 20 d 12 Kerala PET 2012

A atoms construct F C C type structure in which B atoms occupied all the octahedral voids If all the atoms are removed from one of the face of unit cell then total number a atoms left in one unit cells are

In Young s experiment monochromatic light through a single slit S is used to illuminate the two slits S and S Interference fringes are obtained on a screen The fringe width is found to be w Now a thin sheet of mica thickness t and refractive index u is placed near and in front of one of the two slits Now the fringe width is found to be w then 1 w w 3 w u 1 tw 2 ww 4 w W

WOOO 4 Which of the following statement is true in Your experiment separation between the slits is gradu increased 1 fringe width increases and fringes disappear 2 fringe width decreases and fringes disappea 3 fringes become blurred 4 fringe width remains constant and fringes bright more

3 Will be green 4 Will not be formed WO005 57 InYoung s double slit experiment a mica sheet thickness t and refractive index u is introduced the path of ray from the first source S By ha much distance the fringe pattern will be displaced 1 n 1 t d 1 D 3 WO005

4 120 112 ALLEN 46 The number of spectral line obtained in the emission spectrum of H atom in Lyman series when electron jumps from fifth excited state to first excited state is 1 Zero 3 15 2 4 4 10 46

Certain amount of urea is dissolved in 200 g o water in order to decrease the vapour pressure o water by 25 The molality of the solution is 1 1 85 m 2 0 93 m 3 18 5 m 4 9 3 m

Photoelectric effect when yellow light shine by pottasium atom Then electron is emitted But pottasium will not show itself colour Only yellow light is reflected And when red colour no photoelectron is emit And this case pottasium will not show itself colour Only red light is reflected Am I right 2 45 PM

05 A solid cube and sphere are made of same substance and both have same surface area If the temperature of both bodies 120 C then 1 Both will loss of Heat by same rate 2 Rate of loss of Heat of cube will be more than that of the sphere 3 Rate of loss of Heat of the sphere will be more than that of the cube 4 Rate of loss of Heat will be more for that whose mass is more PHYSICS THERMAL PHYSICS EXTROSE PAS

2 The material used in the manufacture of cooker must have K coefficient of thermal conductivity S specific heat of material used 1 high K and low S 3 high K and high S 2 low K and low S 4 low K and high S

e 060 to of 59 In which of the following phenomenon heat convection does not take place 1 land and sea breeze 2 boiling of water 3 heating of glass surface due to filament of the bulb

60 In natural convection a heated portion of a liquid moves because 1 Its molecular motion becomes aligned 2 Of moleuclar collisions within it 3 Its density is less than that of the surrounding fluid 4 Of currents of the surrounding fluid

10m 44 The lengths and radii of two rods made of same 49 The material are in the ratios 1 2 and 2 3 respectively If the temperature difference between the ends for the two rods be the same then in the steady state The amount of heat flowing per second through them will be in the ratio of 1 1 3 2 4 3 3 8 9 4 3 2 temp Ther then 1 3 3 3

I am just unable to understand that over here how can we find the radius of 3rd Bohr orbit of He when orbit of 2nd Bohr orbit of Li 2 is given as x How can we compare the r adius of two different elements I think that with this met hod we can find the radius of any orbit when we are given the value of a particular orbit of same elements but for dif ferent elements can this method be used Please explain Q If the radius of the 2nd bohr Orbit of Lit is x then radius q 3rd Bohr Orbit of Het will be x 0 529X 0 529 3x 344 0 579 x

27 The displacement of a particle starting from rest at t 0 is given by s 61 1 The time when the particle will attain zero again is 1 4s 2 8s 3 12s Se locity 4 16s KN0027 34

displacement of a particle is represented by the 2ng equation s 3t 7t 5t 8 where s is in metres and t in seconds The acceleration of the particle at t 1s is 1 14 m s 3 32 m s 2 18 m s 4 zero

At 300 K 1000 cm of a solution containing 4 34 g of solute shows osmotic pressure of 2 5 atm What is the molar ma of solute R 0 0821 L atm K mol B C 42 75 g mol 82 73 g mol 58 31 g mol 91 65 g mol 1

2 An equiconvex lens has a power of 5 dioptre If it is made of glass of refractive index 1 5 then radius of curvature of its each surface will be 11 30 2 10 2 40 m

114U INI14UH What will be the ESR frequency of an unpaired electron in a magnetic field of 0 33T given that for the free electron ge 2 and u 9 273x10 24 JT a 7 00 GHz b 9 00 GHz c 11 00 GHz d 13 00 GHz 0 33 fant form a 7 00 GHz LE 23a fea fari uma at3 femazo et ER for et femd 2 B 9 273 10 24 JT fa za femaza z b 9 00 GHz Jeait fea c 11 00 GHz d 13 00 GHz