Physical Chemistry Questions

72 Pure PCl is introduced into an evacuated chamber and comes to equilibrium at 247 C and 2 0 atm The equilibrium gaseous mixture contains 40 chlorine by volume Calculate K at 247 C for the reaction a 0 625 atm c 1 6 atm PC15 g PC13 g Cl g b 4 atm d None of these

Q3 A mixture of AIPO4 s and AIPO3 s is shaken with water until a saturated solution is formed Both of the solids remain in excess What is A1 in the saturated solution For AIPO4 Ksp 1 3x10 6 and for AIPO3 Ksp 3 5 10 4

b E ele Evib Erot c Ecle Evib Erot vibration rotation spectra is given by b Av 1 AJ 1 d AJ 1 a E ele X Evib XE rot 17 R branch in a Av 1 AJ 1 c Av 1 AJ 1 1 uhon a ele vib E

a 1 8 c 1 16 4 The cell reaction for the given cell is spontane Pt H H M H M Pt H A a P P c P P b P P d Pj 1 atm of e ampere was passed

Concentration of the Ag ions in a saturated solution of Ag C O4 is 2 2 x 10 mol L 1 Solubility product of Ag C A 2 42 x 10 8 C 4 5 x 10 11 01 B 2 66 x 10 12 D 5 3 10 2

a microwave active b IR inactive c microwave inactive d none of these 14 The selection rule for rigid diatomic molecule for rotational transitions describes d AJ 1 a Av 0 b Av 1 c AJ 0 15 The zero point energy of molecule is given as

1 C B D A Y2 A C B D 3 B D A In context with the industrial preparation of hydrogen from water gas CO H which of the following is the correct statement AIEEE 2008 1 CO is removed by absorption in aqueous Cu Cl Solution 2 H is removed through occlusion with Pd 3 CO is oxidized to CO with steam in the presence of a catalyst followed by absorption of CO in alkali 4 CO and H are fractionally separated using differences in their densities 2 is statements is incorrect regarding physissorptions AIEEE 2009

D K 2 Jog K Surface tension of lyophilic sals is Lower than that of H O 139 B1 2 More than that of H O 4 None of the above Habt from collidal solution the effect due to scattering of light is known as 3 Equal to that of H O try Choice A

6 Consider the following diagram Q 5 to 6 A Which of the following change is physical change 1 only A 2 only B B Which of the following change is chemical change 2 only B 1 only A 3 A and B both DO 3 A and B both 8 4 None of A and B 4 None of A and B

c polarizability d dipole moment The plot of total molar polarization PT vs inverse of absolute temperature 1 T of the system in case of carbon tetrachlloride is a parallel to 1 T axis b parallel to PT axis c passing through origin d with positive intercept on Praxis Expooted value of dingle moment in Debye units in case of p dichlorobenzene is

A metal M which is not affected by strong acids like conc HNO3 conc H SO4 and concentrated solutions of alkalies like KOH and NaOH but dissolves in aqua regia and forms MCI3 which is used for toning in photography The metal M is O Ag OHg O Au CUL

a Zero Dipole moment of water is 1 84 D which indicates that water molecule a linear symmetrical b linear non symmetrical c nonlinear symmetrical d nonlinear nonsymmetrical length range in nmn of microwave radiation is

Ph The rate law for the following intramolecular Cannizzaro reaction will be i i H a rate k Ph c rate K Ph OH 1 8 8 Ph CH ph i i HON H OH www i HITOH d rate k Ph C C H OH b rate K Ph C H OH

Q 10 SINGL The voltage of the cell consisting of Li s and F2 g electrodes is 5 92 V at standard condition at 298 K What is the voltage if the electrolyte consists of 2 M LiF In2 0 693 R 8 314 JK mol and F 1 B C 5 90 V 5 937 V 5 88 V Correct Answer 4 9 V 96500C mol

1 g of a moist sample of a mixture of KCIO and KCI was dissolved in water and made upto 250 mL 25 mL of this solution was treated with SO to reduced chlorate into chloride and the excess SO was boiled off When the total chloride was precipitated 0 1435 g of AgCl was obtained In another experiment 25 mL of the original solution was treated with 30 mL of 0 2 N solution of FeSO and unreacted FeSO required 37 5 mL of 0 08 N solution of an oxidizing agent for complete oxidation Calculate the molar ratio of chlorate and chloride in the given mixture Fe reacts with CIO according to equation CIO 6Fe 6HCl 6Fe 3H O 3

c passing through origin d with positive intercept on PT axis 7 Expected value of dipole moment in Debye units in case of p dichlorobenzene is a zero b one c two d six If bond moment of nitro group is u then expected dipole moment of m dinitrobenzene is 6

The frequency of a wave of light is 12 10 4 s The wave number associated with this light radiation is Question Type Single Correct Type 1 2 3 4 5 x 10 7 m 4 x 10 8 cm 1 2x 10 7 m 1 4 x 104 cm 1

As per Valence Bond Theory V B T which of the following overlapping is are possible Od dy 0 Py F sp on X axis common axis Px Py sp on X axis common axis on X axis common axis on X axis common axis

1 1 2 1023 3 10 AIEEE 2006 In langmuir s model of adsorption of a gas on a solid surface 1 the rate of dissociation of adsorbed molecules from the surface does not depend on the surface covered 0 Um 2 the adsorption at a single site on the surface may involve multiple molecules at the same time 3 the mass of gas striking a given area of surface is proportional to the pressure of the gas 4 the mass of gas striking a given area of surface is independent of the pressure of the gas illoide B Cand D are 0 50 0 01 0 10 and 0 005 respectively The correct IEEE 20081

Total number of enthalpy s out of given nine of M g which is are not associated with conversion of MM LE I E I E L E LE I E EGE EGE EGE I E lonization energy EGE electron gain enthalpy

possible from that state is a 6 b 5 d 15 c 7 Imagine an atom made up of a stationary proton and a hypothetical particle of double the mass of electron but having the same charge as the electron Apply Bohr s atomic model and consider all possible transitions of this hypothetical particle directly to the first excited state The longest wavelength photon that will be emitted has wavelength given in terms of Rydberg constant R for the hydrogen atom equal to E 9 3 5R 36 b 5R c 18 5R d 4 R

The specific conductance of weak acid HA whose concentration 0 1 M is 0 001 ohm 1 cm 1 Its molar conductance is 0 001 0 01 1 0 10 Marks 4 1

For non polar molecules the molar polarization is a deformability c polarizability b induced molar polarization d dipole moment 0 of absolute temperature

to 300 K a 2 g b 3g c 4 g d 1 g gases neon 13 A vessel contains two non reactive monatomic and oxygen diatomic The ratio of their partial pressures is 3 2 The ratio of number of molecules is b c d 3 14 A cylinder contains 10 kg of gas at a pressure of 312 E

For the two reactions I AB II C D following graph is obtained conca IMCI 0 5M A 30 for 60 Time min Which of the following is true If B A then at that time B D If C A then at that time B D t100 Reaction 1 t100 Reaction II 3 2 3 A C at t min M

Mass of KHC O potassium acid oxalate required to reduce 100 mL of 0 02 M KMnO in acidic medium to Mn is x g and to neutralise 100 mL of 0 05 M Ca OH is y g then B 2x y A x y C x 2y D None is Correct SPACE FOR ROUGH WORK

Efficiency of a cell with cell reaction under standard conditions A s B A B s AH 300kJ is 70 The standard electrode potential of cell is O 2 176 V O 2 876 V O 1 248 V 1 648 V

Which of the following phenomena are not justified by wave nature of light a Line spectra of atoms with special reference to hydroge b Variation of heat capacity of solids as a function of temperature c Photoelectric effect d Black body radiation a and b only c and d only b c and d only a b c and d

Given that Ni Ni 0 25 V Cu Cu 0 34 V Ag Ag 0 80 V Zn Zn 0 76 V Which of the following reactions under standard condition will not take place in the specified direction ON Cu s Ni s Cu aq 2Agaq Cu s 2Ag s Cuq Zn s Cu 2 Znaq Cu s 2H aq Zn s H g Znaq

At a given temperature in order for a reaction o be favored spontaneous the reaction should have a relatively A Small AH and a small AS B Large AH and a large AS C Small AH and a large AS D Large AH and a small AS

Question No 4 If enthalpy of combustion of methane is x kJ mol then heat evolved by the combustion of 8 g CH4 is x2 C O x kJ O 8xkJ O 16 x kJ

For a reaction 2A 2B C products with the help of the following table find order with respect to A B C B C A 0 010 0 005 0 010 0 005 0 010 0 010 0 005 0 005 O 3 2 0 O 1 1 0 3 2 1 rate of reaction 0 010 5 x 10 3 0 015 5 x 10 3 0 010 1 x 10 2 0 010 25 10 3

All stion No 6 moles of gas compressed reversible from 10 L to 1 L at constant temperature The entropy change during the process is 10 R D 10 R Physics 23 03 R O 23 03 R CP

In the beginning of the reaction A B C 2 moles of A are taken out of which 0 5 mole gets dissociated What is the amount of dissociation of A 1 0 5 2 1 3 0 25 4 4 2

Suppose 5 272 g of a soil sample undergoes an extraction with 50 mL of extracting solvent to remove the potassium This 50 mL is then diluted to 250 mL and tested with an instrument The concentration of potassium in this diluted extract is found to be 35 7 ppm What is the potassium concentration in parts per million in the untreated soil sample O a 1000mg kg O b 125ppm O c 1692 90mg kg O d 2090mg kg

Acidulated water on being electrolysed for some time the total volume of oxygen and hydrogen liberated is 16 8L when measured at NTP In this process charge utilized is found to be x Farads Find x

e 3 A solid is made of two elements X and Y Atoms X are in fcc arrangement and Y atoms occup all the octahedral sites and alternate tetrahedral sites What is the formula of compound

3 In which cell liquid function potential need to be eliminated a Pt H2 A HC1 Pt H2 P Pt H HC1 HC1 Pt H C1 C2 CHE c Nicad cell d Lond storage battery I mill Tivo liq present Ag mg cl

0 4 Sulphuryl chloride SO Cl reacts with H O to give mixture of H SO and HCl Aq solution of one mol SO Cl will be neutralised by 4 A 3 mol of NaOH B 2 mol of Ca OH C both D None O A OB O C

Question No 9 If enthalpy of combustion of C s H g and C H6 g are x y and z kJ mol respectively then enthalpy of formation of ethane will be O x y z Oz x y Oz 2x 3y O 2x 3y Z

The heat of at 27 C combustion of benzene measured by bomb calorimeter for the reaction C6H6 e 7 02 g 6CO2 g is 780 kcal 1 mol The heat evolved on on burning 39 g of benzene at 27 C in an open vessel will be A 230kcal B 780kcal 390 45kcal 190 51ool

The minimum uncertainty in de Broglie wavelength of an electron accelerated from rest by a potential difference of 6 0V if the uncertainty in measuring 1 the position is nm is TU a 6 25 c 0 625 b 6 0 d 0 3125

5 0 m mol dm 3 aqueous solution of KCl has a conductance of 0 55 ms when measured in a cell of ell constant 1 3 cm 1 The molar conductivity of this solution is mSm mol 1 Round off o the Nearest Integer Answer

For electrolyte AxBy The relation between vant hoff factor and degree of dissociation can be given as i 1 x y 1 i 1 a xa ya 1 i 1 x y a a All of these Marks 4 1

Standard enthalpy of vaporisation AvapH for water at 100 C is 40 66 kJ mol The internal energy of vaporisation of water at 100 C in kJ mol is a 37 56 b 43 76 c 43 76 d 40 66 Assume water vapour to behave like an ideal gas

metals is generally a slow electrochemi cal reaction involving many steps These steps in volve electron transfer reactions A particular type of oxidation involve overall first order kinetics with re spect to fraction of unoxidised metal 1 f surface thickness relative to maximum thickness T of oxidised surface when metal surface is exposed to air for con siderable period of time 3 In 1 A Rate law df dt 200 hrs t k 1 f where f of oxide film at time t T thickness of oxide film at t 0 8 A graph of In 1 f vs t is shown in the adjacent figure 41 The time taken for thickness to T X thickness

BOX 3 The equilibrium constant K for the reaction 2HCl g H g Cl g is 4 x 10 34 at 25 C What is the equilibrium constant for the reaction 1 2 x 10 17 H g Cl g HCl g 2 2 2 2 5 x 1033 3 5 x 106 4 None of these

Select the incorrect statement among the following regarding photoelectric effect E There is no time lag between the striking of light and ejection of electrons The number of ejected photoelectrons do not depend upon the frequency of light Below the threshold frequency the photoelectrons cannot be ejected The kinetic energy of photoelectrons is proportional to the intensity of light

In a sample of hydrogen atoms all the atoms are in a particular excited state If the emission spectrum of this sample has only 4 spectral lines in the visible region then the total number of spectral lines in IR region possible from that state is a 6 b 5 c 7 d 15 of double the mass of electron

0 23 10 19 d 0 32x10 25 In the electrolysis of CuCl2 solution using Cu electrodes the mass of cathode increases by 3 18 g What happened at the other electrode a 0 05 mole of Cu b 0 112 litre of Cl2 was liberated Iions passed into solution c 0 56 litre O2 was liberated d 0 1 mole of Cu2 ions passed into the solution fH is M 2