Physical Chemistry Questions

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

The reduction potential of silver electrode in Ag CrO4 solution Ksp 4x solution at 25 C will be Eg Agt 0 80 V 0 80 0 80 0 80 0 80 0 0591 1 0 0591 1 0 0591 1 0 0591 log x log 2x log 2x log 2x

4 None of the above 5 I II and III are three adsorption isotherm at three temperatures T T and T where x is the amount of adsorbate adsorbed on m g of the adsorbent Temperatures T T and T3 are in the order 1 T T T3 3 T3 T T XIE m p 2 T T T3 4 No specific order T T T3

79 For NaCl crystal the sublimation Energy of Nais 108 5 KJ 79 NaCl 3 13 TAH Chemical Bondin 11 Bond dissociation energy of Cl is 243 KJ lonization energy 2 of Na is 495 2 KJ and electron affinity of Cl is 348 3 KJ and lattice energy of NaCl crystal is 758 7 KJ Calculate the value of AH for NaCl Cl 1 281 8 KJ mole 2 381 8 KJ mole 3 265 8 KJ mole 4 395 3 KJ mole nic Na 108 5 d Na 492 21 Na t 243 cl 384 3 CL N 243 K 348 3 KJ NaCl3 758 7 KJ 1 281 8 KJ mole 2 381 8 KJ mole 3 265 8 KJ mole 4 395 3 KJ mole 108 5 KJ Cl 495 2 KJ CScacia y 1187 0 74 3 7

ENGLISH Q No 55 Single Correct A A Marks 4 00 1 0 x g is the amount of a gas adsorbed by mg of a solid If multilayer adsorption is supposed to occur then which of the following statement is correct A B C D At low pressure x m increases more than proportionally to gas pressure At low pressure x m increases less than proportionally to gas pressure At moderate pressure x m increases more than proportionally to gas pressure At high pressure x m becomes independent of gas pressure

2 381 8 KJ mole 3 265 8 KJ mole 4 395 3 KJ mole 30 Ionic compound in which cation and anion are bonded by 80 ff for minimum force of attraction mg 1 Na N Mg3N 3 Ca3N 4 BeO 108 5 un Na 492 21 J Na Ca Atsomot that man Amie the comprent have traiti 1 281 8 KJ mole 2 381 8 KJ mole 3 265 8 KJ mole 4 395 3 KJ mole 1 Na N 2 Mg3N 3 Ca3N 4 Beo 758 7 K 1187 0 74317 1107 15 43 2 353 3

d None of these sp 118 In a saturated solution of AgCl NaCl is added gradually The concentration of Ag is plotted against the concentration of Cl The graph appears as a Ag cr b Ag CI c Ag cr d Ag cr

8 Select the correct statement s 1 A hydrophilic colloid is a colloid in which there is a strong attraction between the dispersed phase and water 2 A hydrophobic colloid is a colloid in which there is a lack of attraction between the dispersed phase and water 3 Hydrophobic sols are often formed when a solid crystallizes rapidly from a chemical reaction or a supersaturated solution 4 All of the above

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

ion C 1 A 1 a d 2 b c 3 a b d 4 a b c d 59 The half life period of a second order reaction is 30 minutes If the initial conc is 0 1 M the rate constant will be 1 0 666 mol L min 2 0 333 mol L min 3 0 444 mol L min 4 0 555 mol L min

For a strong electrolyte the difference between molar conductivity Am and limiting molar conductivity A is equal to A Ac B Ac C Acalleol D Ac 2 where A is a constant and c represents concentration

4 FeCl3 Fe 3OH 3 A sol has positively charged colloidal particles Which c the following solutions is required in lowest concentratic for coagulation 1 NaCl 3 ZnCl 2 K4 Fe CN 6 4 Na SO4

cal adsorption 1 increases with increase in temperature 2 decreases with increase in temperature 3 first increases then decreases with increase in temperature 4 first decreases then increases with increase in temperature

b 2 5 x 10 2 c 2 5 10 8 121 The solubility of a sparingly soluble salt A B in water is S moles per litre The solubility d 2 5 x 10 10 y c x yYsx y d sx y product has the value a s b x y S y 122 What is the molarity of a saturated colutio

A tube of length 50 cm is containing a gas in two sections separated by a mercury column of length 5 cm as shown in figure The open end of tube is just inside the Hg surface in container find pressure difference of gases in two sections Assume atmospheric pressure 75 cm of Hg column 10cm G Sum G P 75cm of Hg 5cm 30cm 271 G then

electron and the nucle us as ris similar to the gravitational force However when a body is moving in an orbit it undergoes acceleration even if it is moving with a constant speed in an orbit because of changing direction So an electron in the nuclear model describing planet fike orbits is under acceleration According to

all Enzyme catalysis enzyme mechanism homogenous and heterogeneous catalysis and adsorption theory of heterogeneous catalysis catalyst related any chemical reaction All are example o chemical adsorption 11 17 AM

Chemical Bonding 6 The correct sequence of increasing covalent character is 6 may c add 33 34 fuh Gri wila Gila represented by Brf3 1 LICI NaCl BeCl 2 BeCl LICI NaCl 3 NaCl LiCl BeCl BeCl NaCl LICI CHL 160 35019 1 LiCl NaCl BeCl 2 BeCl LICI NaCl 3 NaCl LICI BeCl 4 BeCl NaCl LICI F Brif C P L

59 The incorrect statement is 1 p have two nodal planes 2 Bond order of HeH is 0 5 3 In NCO C is sp hybridised 4 O is polar while O is non polar 2 Whi 0 A 4 0 Cl dz 69 1 p 2 HeH 0 51 3 NCO C sp 1 4 0 0

31 A solid AB has NaCl type of ideal crystal structure 3 with packing efficiency of 79 If all atoms along a body diagonal are removed Then new packing efficiency of solid would be 1 79 2 73 1 3 68 2 4 60 4

65 Molecular orbital electronic configuration of Be2 will be 65 Be a KK o 2s b KK o 2s o 2s c o 1s o 1s o 2s o 2s d o 1s o 1s o 2s 2p Correct answer is 1 a b 3 c d GS 2 b c 4 a c 14 15 16 10 hond length in H Q and Bonding chaich scarifich farina a KK o 2s b KK o 2s o 2s c o 1s o 1s o 2s o 2s d o 1s o 1s o 2s 2p HEY AR 1 a b 3 c d 66 O H O O 2 b c 4 a c

For phase transformation of A 90 gm mole 4 4 1 Densities of A s and A 1 are 0 9 gm ml and 1 0 gm ml respectively Standard melting point of A 27 C AG 300 300 J mol AH 300 2700 J mol A AG 2 bar 300 K 301 J mol B AG 2 bar 300 K 299 J mol AS 300 10 J mol K CO

the en CH 119 K of AgCl is 1x 10 10 Its solubility in 0 1M KNO will be a 10 5 moles litre b 105 moles litre c 105 moles litre d None of the 120 50 mL of a solution containing 10 3 mole of Ag is mixed with 50 mL of a 01 M HCL C

au Find the temperature at which 3 moles of SO will occupy 3 O 1510 1 a volume of 10 litres at a pressure of 15 atms a 6 71 atm lit mol 2 b 0 0564 lit mol 1 350 5724 C 2 250 5724 C 3 150 5724 C m 3 P 1504 V 1024 273 4 450 5724 C The ability of an ion to bring about coagulation of a given 2 267 PARA a 6 71 atm lit mol 2 b 0 0564 lit mol 1 1 350 5724 C 2 2 250 5724 C 3 150 5724 C 4 450 5724 C 1 PVC MRT X5 X 80 x 3 x 3X25 Hafan find PCBZ 1 to 3 z

An electric current is passed through two solutions of 1 AgNO and ii a solution of 10g CuSO4 5H O crystals in 500 mL H O platinum electrodes being used in each case After 30 minute it is found that 1 307g Ag has been deposited What was the conc of Cu expressed in g of Cu per litre in solution after electrolysis

9 KCI crystallises in the same type of lattice as does NaCl Given that r r 0 55 and Na k 0 74 r K Na calculate the ratio of the side of the unit cell for KCI to that for NaCl 1 1 122 2 2 122 3 1 414 4 0 732 12 1 4 3 107

aliks Solid AB has NaCl type structure If the radius of A and B are 0 5 and 1 5 respectively and formula mass of AB is 48 g mole what is the density in gm cm of AB solid Take Avogadro s number 6 x 1023

Which of the following aqueous solution will have the highest freezing point NCERT Pg 58 1 0 1 m NaCl solution 2 0 1 m Sugar solution 3 0 1 m MgCl solution 4 0 1 m AICI solution

56 The mass of silver eq mass 108 displaced by that quantity of current which displaced 5600 mL of hydrogen at STP is a 54 g c 5 4 g The tima 0 118 d E E2 0 118 b 108 g d none of these of 80 cm wit

Which of the following is correct from of Freundlich adsorption isotherm equation O XE kpl n n m kp1 n 1 kp1 n 0 1 0 0 1

The product of PV is plotted against P at two temperatures T and T2 and the result is shown in the figure What is correct about T and T PV A B C D P bar T1 T2 T2 T1 T1 T T T2 1 T T

A particle is projected with speed 50m s at an angle 370 with the horizontal and it touches an inclined plane of inclination 300 as shown in the figure Height of the point form the ground 11n RINKI where particle touches the incline is given as Find n 3 g 10m s2 30 37

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

c 6912 S d None of these 124 The solubility of electrolytes MX MX2 and MX3 is 1x 10 3 moles per litre Hence the respective solubility products are a 10 4 x 10 27 10 12 c 10 8 10 8 32 10 2 x b 10 4x10 32 10 2 d None of these

65 Dipole moment of CI 11 1 D 2 4 4 D 3 3 3 D 4 2 56 D is 1 1 D hence dipole mo 65 ment of given compound will be CI CI Ca CI 1 1 1 D 2 4 4 D 3 3 3 D 4 2 56 D CI CI 1 1 De fa fa g CI

12 A reddish brown sol is obtained by adding small quantity of FeCl3 solution to freshly prepared and well washed Fe OH 3 ppt Fixed layer and mobile layer are represented as 3 1 FeCl3 Fe 2 Fe OH 3 Fe 3 Fe OH 3 Fe 4 FeCl Fe 3 OH CI 3C1 3OH

For the reaction H COCO H O if the initial concentration of H CO and x moles litre of hydrogen is consumed at equilibrium the correct expression of K is 3 1 x 2 x 1 x 1 x 1 x

1 4 37 x 10 m s 2 4 37 x 106 m s 3 8 73 x 108 m s 4 8 73 x 108 m s 78 The transition of electrons in hydrogen atom having 78 466 minimum wavelength is 1 M 3 J 2 38 x 4 2 2 have same wavelength 2 4 37 3 8 73 x 108 m s 4 8 73 x 108 m s F 1 n 3 n5n4 2 3 4 4 84 What is the of Hetion 16 1 3R 3 GC

In an organic compound hydrogen is 2 9 times of C present and oxygen is 4 times of hydrogen present by mass The empirical formula of the compound is O C4H O O C HgO3 O CsH O3 O C3HgO Marks 4 1

4 n a e p g 600X10 4 n c 54 The frequency of yellow light having wavelength 600 nm is 54 a g 15 0 x 10 4 Hz 2 2 5 107 Hz 1 5 0 3 5 0 x 107 Hz 4 2 5 x 10 4 Hz 3 5 0

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

1 2 the pair of position isomers Et COOH OH 3 4 Both 1 and 2 and and CICIE OH H C C C COOH C C C 8 2 6 2 and Et C C CC C C C C C

The correct option that represents an ideal solution formed upon mixing two liquids is A Amix H 0 Amix V 0 Amix G 0 Amix V 0 Amix B Amix H 0 G 0 C Amix H 0 Amix V 0 Amix G 0 D Amix H 0 Amix V 0 Amix G 0

Mass of solvent 13 467 g Mass of solute 2 064 g Freezing Point of solvent 43 4 degrees Celsius Freezing Point of solute 41 5 degrees Celsius Kf freezing point depression constant 4 53 degree Celsius m Questions a Find Delta T using the freezing points b Find molality of solution w unknown solute already dissolved into solvent c Find moles of unknown solute in solution d Find the molar mass of unknown solute

61 For pure water pH 7 Kw at 298 K is 10 14 On adding some acid to it its pH changes to 3 Then the value of Kw is 1 10 11 3 10 6 2 10 14 4 None of these

81 If lattice energy of sodium chloride is U then lattice energy 8 man attraction of magnesium chloride is 1 2U 2 4 U 3 6 U 4 None Which 7 wal U ngch

5 In a first order reaction the concentration of the reactant decreases from 0 8 M to 0 4 M in 15 minutes The time taken for the concentration to change from 0 1 M to 0 025 M is 1 60 minutes 3 7 5 minutes 2 15 minutes 4 30 minutes The rate for a first order ropotion C

U where m is the mass of the electron and the velocity associated with the ejected electro Lastly a more intense beam of light consist of larger number of photons consequently th number of electrons ejected is also larger a compared to that in an experiment in which beam of weaker intensity of light is employed stee A fo S Dual Behaviour of Electromagne Ene 3 19 Pro A1 ligh nur by t

f Both KCl and acetic acid have values of AT b and AT in water which deviate from the values obtained from the constants K and K and the value of molality of the solutions as the interactions of the two solutes with water are different For the same molality of the solutions of KCl and acetic acid you expect A AT KCI AT acetic acid B AT KC1 AT acetic acid C AT KCI AT acetic acid b D AT KCI AT acetic acid

a TTFTT b FTTTF c TFTFT d FFTTT 116 A 1 litre solution containing NH4Cl and NH4OH has hydroxide ion concentration of 10 6 mol litre Which of the following hydroxides could be precipitated when the solution is added to 1 litre solution of 0 1 M metal ions I Ba OH 2 Ksp 5 10 III Mn OH 2 Ksp 2 10 3 a I II IV b IV II Ni OH Ksp 1 6 10 6 2 IV Fe OH 2 Ksp 8 x 10 16 c II and IV d II III IV