Physical Chemistry Questions

Calculate the of radiant energy converted into kinetic energy of x atoms x atom forms afte dissociation of X molecules by the absorption of 5 quantum of radiation having wave lengt 5000 A If bond energy of X molecules is 250 KJ mol

if 10 What is the potential of the cell containing two hydrogen electrodes as represented below Pt H g H 10 M H 0 001 M H g Pt 1 0 295 V 13 0 295 V 2 0 0591 V 4 0 0591 V col

75 The plot of In Kea versus versus inverse of a reaction is shown as eq ba In K T K K K L T T2 The reaction should be 1 Endothermic 2 With no change in enthalpy 3 Exothermic 4 Always spontaneous 1 In ut

39 50 How many unit cells of KBr are present in Imm volume of KBr KBr M 119 crystallizes in NaCl type of crystal lattice and its density is 2 75 g cm 1 2 78 x 10 9 2 6 02 x 102 3 3 4 x 10 8 4 None of these An atomic solid has hexagonal arrangement of

NX is produced by the following step of reactions M X MX 3MX2 X M3X8 M3X8 N CO3 NX CO2 M304 How much M metal is consumed to produces 206 gm of NX Take at Wt of M 56 N 23 X 80 A 42 gm C 14 3 gm B 56 gm D 7 4 gm

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

c CIT 114 Given below are the half cell reactions VMn 2e Mn E 1 18 V 2 Mn 3 e Mn Mn 2 E 1 51 V The E for 3Mn 2 Mn 2Mn 3 will be a 2 69 V the reaction will not occur b 2 69 V the reaction will occur c 0 33 V the reaction will not occur d 0 33 V the reaction will occur

b Fe 1 Fe s Above equilibrium is favoured at High pressure and low temprature 2 High pressure and high temperature 3 Low pressure and high temperature 4 Low pressure and low temperature 7 For the reaction N g O g 2NO g PEDRY 46 Fe 1 Fe s 1 2 3 4 Chemical fff Equilibrium 37N g O g 2NO g

5 A concentration cell is constructed by dipping copper rod in 0 002M and 0 2M copper sulphate solution respectively Write cell representation cell reaction and calculate EMF of cell

Nitromethane Fuel having a chemical formula CH3O2N is burned in an engine at a fuel air equivalence ratio of 0 88 and a temperature of 990 K The molar fraction of CO2 is Select one a 0 472 b 0 518 c 0 247 d 0 158 e 0 089

Which of the following is not disproportionation reaction 1 P NaOH NaH PO PH 2 BaC N Ba CN 3 Hg 1 Hgl Hg 4 Cl 20H CIO The ratio of macres of Cl H O alament A attached

The change in boiling point of a solution containing 1 40 mol of KCN in a kg of water is AT On additio of 1 80 mol of Hg CN 2 all KCN reacts to form Hg CN 42 and change in boiling point is observed as AT 2 Calculate the ratio of AT AT

s over solvent pressure has ative aspect of solubility of a gas with pressure has been ble effect on the solutions of solids and liquids The terms of Henry s Law y s Law Sunt of gas dissolved w per unit volume of solvent is proportional to its pressure PA i e XA A or XA KHPA where units of k is bar or atm e above result is sometimes also written as PA or PA KH XA XA Slope k atm gas ts pressure har inits of k is atm or bar pressure of the gas over the solution onality constant known as Henry s law constant w constant is different for each gas solvent dissolved per unit mass of solvent e of Cas K i Temp Ku k bar Application of Henry s Law a In the production of carbonated beverages Why cold drink water bottles are sealed under high pressure According to Henry s law solubility of gas increases with increase in pressure of the solution that is why cold drink bottles are sealed under high pressure so that more CO can be dissolved in it b In the deep sea diving For those people who do deep sea diving nitrogen and oxygen get dissolved in their blood under the effect of pressure of water This dissolved oxygen gets utilized in the metabolic activities but nitrogen remains as such When a person comes out of the sea this nitrogen which was dissolved in blood comes out in the form of bubbles which is very painful This is called de compression sickness c Combination of hemoglobin and oxygen in lungs Lungs oxygen Hb Oxy Hb Tissues Partial pressure is low When air enters lungs partial pressure of the oxygen is high This oxygen combines with hemoglobin to form oxyhemo globin but the tissues has less partial pressure of oxygen Thus in tissues oxyhaemoglobin breaks into oxygen and this released oxygen is used in metabolic activities ILLUSTRATION 8 7 If N gas is bubbled through water at 293 K how many millimoles of N gas would dissolve in 1 liter of water Assume that N exerts a partial pressure of 0 987 bar Given that Henry s law constant for N at 293 K is 76 84 kbar Solution The solubility of gas is related to its mole fraction in the aqueous solution The mole fraction of the in the solution gas uloted by applying Henry s law Thus

a og c 2 g 4 116 For the following electrochemical cell at 298 K Pt s H g 1 bar H aq 1 M M aq M Ecell 0 092 V when M aq 10 2 M4 aq 03 RT F Given E4 M2 0 151 V 2 303 The value of x is a 2 c 1 b 1 d 2 aq Pt s 0 059 V

Perovskite is a mineral composed of calcium titanium and oxygen cations of titanium lie at the body centre oxide ions at the face centres and calcium ions lie at corners of a cubic lattice The simplest formula of the mineral is 1 CaTiO 3 CaTi 0 2 CaTi O 4 CaTiO

1 mole of electrons are transferred during electrolysis consider only electrolysis of water in both compartments pKa pKa values of H CO3 are x y respectively pH of anode cathode respectively after electrolysis SRAMA EVA AYATHE 1 lit solution of Na CO3 NaHCO3 1 lit solution of Na CO3 NaHCO3

3 5 33 10 4 None of these 30 mL of a gaseous hydrocarbon requires 90 mL of oxygen for complete combustion and produces 60 mL of CO then the molecular formula of hydrocarbon is 1 C H 2 C H 3 C H 4 C H

Consider the following spontaneous reaction 3X g 2X3 g What are the sign of AH AS and AG for the reaction SUF AUFT 1 ve ve ve 2 ve ve ve 3 ve ve ve 4 ve Ave ve 16 3 3X g 2X3 9 AH AS AG fara at 83 1 ve ve ve 2 ve ve ve 3 ve ve ve 4 ve ve ve 8 1 to 3 m 2 3 DS

appropriate number of significant figures Solution Radius of sphere r 1 141cm Volume of sphere Express its volume to an 1111 4 significant figures x 3 14 1 41 cm 11 736cm 3 11 72cm into 4 significant figures

127 Silver ions are added to a solution with Br Cl CO AsO 0 1M Which compound will precipitate with lowest Ag a AgBr K 5 10 13 sp c Ag 2CO3 Ksp 8 1 10 2 b AgCl Ksp 1 8 10 0 d Ag 3 AsO 4 Ksp 1x 10 22

45 The variation of solubility of four different gases G1 G2 etc in a given solvent with pressure at a constant temperature is shown in the plot Solubility G4 G3 G2 Pressure G1 The gas with the highest value of Henry s law constant is a G4 c G3 b G2 d G1

are they two type of acceleration when they absorb electromagnetic radiation they highly acclerated and when they donot absorb electromagnetic radiation they are not highly acclerated but its own acclerated for which there is no chance it s stability 15 48

68 Which of the following molecule has longest C C bond 68 r length 1 CH C CH 2 CH CH CH CH 3 3 CH3 C CH CH 1 CH3 4 CH3 C CH

The nucleus of the element having atomic number 25 and atomic weight 55 will contain CPMT 1986 MP PMT 1987 a 25 protons and 30 neutrons b 25 neutrons and 30 protons c 55 protons

49 Which of the following resonating structure contributes 49 A SERIE ERCAN BAIE BE equally to the resonance hybrid 1 CHg C CH CH CH3 CH3 CH3 C CH CH CH3 CH3 2 CHO C NH CHI CINH O 3 CH C 00 CH C 00 O MAAR 1 CH3 C CH CH CH CH CH CH3 C CH CH CH3 CH3 2 CHg C NH2 CHI C NH O 00 3 CH C tan Batch PCBZ 2 C 8 00 CH C 00 0

180 A vessel contains 14 g 7 moles of hydrogen and 96 93 180 14 g 7 moles of oxygen at STR Chemical reaction is induced by passing electric spark in the vessel to produce water till one of the gases is consumed completely The temperature is brought back to it s starting value 273 K The pressure in the vessel is 1 0 1 atm 2 0 2 atm 3 0 3 atm 4 0 4 atm 0 lm Spark STP gr f ER EMI ga 1 0 1 atm 2 0 2 atm 3 0 3 atm 4 0 4 atm 273Kata FORT PVETRT at O 10x25

Solve the following problems Show your solution 1 What is the pH of 0 0235 M HCL solution 2 What is the pOH of 0 0235 M HCL solution 3 A solution with a H concentration of 1 00 x 10 7M is said to be neutral Why

Inversion of a sugar follows first order rate equation which can be followed by noting the change in rotation of the plane of polarization of light in a polarimeter If Too Tt To are the rotations at t t t and t 0 then first order reaction can be written as a k log k log log log b c k d k rt to TO Tx 70 7x TI TO Too TO Too Tt Too Tt

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

The following results were obtained during kinetic studies of the reaction 2A B Products The time in minutes required to consume half of A is 1 5 1 10 Exp 1 2 3 A in mole L 0 10 0 10 0 20 B in mol L 0 20 0 25 0 30 Initial rate of reaction M min 6 93 x 10 6 93 x 10 1 386x102

a 8 10 b 6 4 x 10 c 8 10 130 The solubility of Ba 3 AsO 4 2 formula mass 690 is 6 9 x 10 2 g 100 mL What is the Ksp a 1 08 x 10 11 b 1 08 10 13 X c 1 0 x 10 15 d 6 0 10 13 131 The solubility of AgBrO formula mass 236 is 0 0072 g in 1000 mL What is the K

105 The standard electrode potential of Zn Zn is 0 76 V and that of Ca2 Cu is 0 34 V The emf V and the free energy change kJ mol respectively for a Daniel cell will be a 0 42 and 81 b 1 1 and 213 c 1 1 and 213 d 0 42 and 81

On dissolution of NH Cl in water pH of water decreases It is due to hydrolysis of H 1 NH ion 2 CH ion 3 Both NH and CH ion 4 No hydrolysis takes place NHuel M 0 to NH NM CINECL Hitech H

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

Two aqueous solution of glucose having osmotic pressure 3 atm and 1 5 atm at 300K are mixed in volume ratio 1 2 to form a final solution Calculate elevation in BP of this solution at 300K Given K for H O is 1 8 K kg mol Assume m M Give answer as 20 x AT Use R 0 08 atm litre mol K

60 Calculate Am of oxalic acid given that Aeq Na C O 400 2 cm eq 0 Am H SO4 700 cm mole 8 Aeq Na SO 4502 cm eq 1 400S cm mol 2 600S cm mol 3 800S cm mol 4 None Forth 0 crof Cr o O Komnou ni 2 MP Mn IND 6 2 1 5

57 Bond dissociation enthalphies of H g and N g are 436 0 kJ mol and 941 8 kJ mol respectively and enthalpy of formation of NH3 g is 46 kJ mol What is enthalpy of atomization of NH g 1 390 3 kJ mol 3 590 kJ mol 2 1170 9 kJ mol 4 720 kJ mol

Count the number of correct statements i Minimum potential required for electrophoresis is called zeta potential ii Tyndall effect increases with increase in difference in size of particle and wavelength of light used iii Minimum amount of electrolyte in millimoles per 100 ml required to caus precipitate in two hours is called coagulating value iv Both physical and chemical adsorption decreases with temperature v Chemical bonds may be covalent or ionic in chemical adsorption vi Zeolites are shape selective catalyst

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

In the following reaction Cu H O 3 OH Al H O Cu H O AI H O OH A B C D A A is an acid and B the base B A is a base and B the acid C C is the conjugate acid of A and D is the conjugate base of B D C is conjugate base of A and D is the conjugate acid of B

A Match the statements to the correct question tags 1 Hamida can t whisper 2 3 They hadn t been polite She looked very happy I shouldn t have gone there The sun shone brightly He was rude I am present It hasn t been corrected 4 5 6 7 8 9 You aren t feeling ill 10 They haven t been informed a wasn t he b have they c are you d aren t l e didn t it f can she g should I h has it i didn t she j had they

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

2 moles of benzoic acid and 5 moles of benzene are mixed together to form a solution Which is the solute and which is the solvent O solute benzene benzoic acid solvent water impossible to determine solute benzene solvent benzoic acid Osolute benzoic acid solvent benzene

A liquid is kept in a closed vessel If a glass plate negligible mass with a small hole is kept on top of the liquid surface then the vapour pressure of the liquid in the vessel is A More than what would be if the glass plate were removed B Same as what would be if the glass plate were removed Less than what would be if the glass plate were removed

HCHO Carbon monoxide on reaction with H in the presence of cobalt catalyst gives CH3OH hr CH3COOH m

is incorrect 1 d20 d30 dso d vapour density of Equilibrium mix at certain decomposition 2 43 4 D Initial vapour density 1 2 d Vapour density of Equilibrium mixture 2 1 a 2 x Anital t D

56 If the angle of incidence of X ray of wavelength 3 which produces a second order diffracted beam from the 100 planes in a simple cubic lattice with interlayer spacing a 6 is 30 the angle of incidence that produces a first order diffracted beam from the 200 planes is a 15 b 45 c 30 d 60

Which of the following statements is are correct A At low temperatures hydrogen can be adsorbed more than deuterium on metal surface B Activation energy of deuterium is more than hydrogen in its reaction with halogen C Both H H and D D bond lengths are same D Heat of fusion of deuterium is more that of hydrogen

Tl s Tl 0 0001 M Cu 0 01M Cu s 0 83 V The emf of this cell will be increased by 1 Increasing the concentration of Cu 2 ions 2 Decreasing the concentration of Tl 3 Increasing the concentration of both 40 1 2 both