Physical Chemistry Questions

30 mL of 0 2 N BaCl2 is mixed with 40 mL of 0 3 N Al2 SO4 3 How many g of BaSO4 are formed A 0 10 g 0 60 g 0 90 g D 0 70 g

48 For the disproportionation of copper 2Cut Cu Cu E is Given E for Cu Cu is 0 34 V and E for Cu Cut is 0 15 V 1 0 49 V 3 0 38 V 2 0 19 V 4 0 38 V

Determine the order of reaction its rate The half life period of decomposition of a compound is 50 minutes If the initial concentration is halved the half life period is reduced to 25 minutes What is the order of reaction OF BATE CONSTANT USING DIFFERENT PARAMETERS

isplacement of Mg by iron from MgSO4 solution 4 Alum is the name used for all double salts having the composition M SO4 M SO4 3 24H O Where M stands for Al 3 Cr 3 Fe 3 while M stands for 1 Li Cut Ag 3 Na K Rb 4 Ca 2 Mg 2 Sr 2 2 Lit NH Na 4

Consider the following reaction between zinc and oxygen and choose the 3 points correct options out of the options given below 2 Zn s O2 g 2 ZnO s AH 693 8 kJ mol 1 O The enthalpy of two moles of ZnO is more than the total enthalpy of two moles of Zn and one mole of oxygen by 693 8 kJ O The enthalpy of two moles of ZnO is less than the total enthalpy of two moles of Zn and one mole of oxygen by 693 8 kJ O 693 8 kJ mol 1 energy is evolved in the reaction O 693 8 kJ mol 1 energy is absorbed in the reaction

Which one of the following statements regarding paracetamol overdose is false O O O O O Headache The toxic metabolite in paracetamol overdose is NAPQI O Kidney injury by metabolite Patients getting anticonvulsant

1805 Question No 3 40 In 20a consecutive first order reaction 46989 20200646 A B2C Where k and k are respective rate constant species B has transien existence therefore AO K k BOK 2k cok k DO K K 2020064696 21 0064696 202006 1696 2020064696 6 201

308020103 Question No 30 40 Species A undergoes a unimolecular reaction as follows A A A A k 1 AP For this reaction the first order rate constant at high pressure is k The first 2000 order rate constant become ko 96 2 064 First order rate constant 476 2020 20200 020064696 202006465 A 2 The value of k will be AO K A kx 9 v y when pressure of A is A 1 PA 064696 2020064696 20 96 2020064696 2020064 20064696 2020 2521

The following Absorbance vs concentration of nitrite graph is obtained for a set of data Absorbance 1 8 1 6 1 4 1 2 1 0 8 0 6 0 4 0 2 C 86 Absorbance Vs Concentration y 1 6628x 0 0373 R 0 9893 0 0 2 0 4 0 6 0 8 Concentration of nitrite mg L 1 Determine the concentration of unknown solution for which the absorbance is determined

of 1 atm 0 1 mol of He and 1 0 To an evacuated vessel with movable piston under extern reduced Considering the ideal gas be an unknown compound vapour pressure 0 68 atm at 0 C are the total volume in litre of the gases at 0 C is close to ash

a When SO2 is passed through the saturated solution of H2S The following reaction occurs SO2 2H2S 2H2O 3S In this reaction Which substance is i Oxidized ii Reduced iii Oxidizing agent iv reducing agent 2 b With the help of a labelled ray diagram describe how a converging mirror can be used to obtain an enlarged upright image of an object 2

8020103 stion No 22 40 Reactions in which molecules absorbing light do not themselves re induce other molecules to react are called AO Reversible reactions BO Chain reactions CO Photochemical reactions DO Free radical reaction

ICQ 100 936 The equivalent weight of CH COOH is O A 20 B 15 c 60 0 45

in H S 504 original mixture IIT J 8 To a 25 mL H O solution excess of an acidified potassium iodide was added The iodine liberate 20 mL of 0 3 N sodium thiosulphate solution the volume strength of H O solution UT J An aqueous solution containing 0 10 g KIO weight 214 0 was treated with an excess of K The solution was acidified with HCl The li consumed 45 0 mL of thiosulphate solution to de the blue starch iodine complex Calculate the m the sodium thiosulphate solution IIT JE How many millilitres of 0 5 M H SO4 is needed t 4 IIT JE 0 5 g of copper II carbonate

Stability constant is more for the complex A Ag NH3 B C Cu NH skipped Ag CN D Co NH3 6

Jestion No 40 40 The number average molar mass M and weight average molar mas of a polymer sample are 2700 and 3148 respectively The polydispersity in PDI of the polymer is A 0171 0 3 41 614 ST

gases Column I A Hydrogen gas P 200 atm T 273 K B Hydrogen gas P 0 T 273 K C CO P 1 atm T 273 K n ONL Column II p Compressibility factor 1 q Attractive forces are r PV nRT 6 D06 IIT JEE hinant

5 Which of the following statement is not true about the hexagonal close packing 1 Point O The cordination number is 12 It has 74 packing efficiency O Tetrahederal voids of the second layer are covered by the spheres of the third layer In this arrangement spheres of the fourth layer are exactly aligned with those of the first layer

21 A solution of urea mol mass 56g mole boils at 100 18 degree celcius at the atmospheric pressure If Kf and Kb for water are 1 86 and 0 512 K Kg mole respectively the above solution will freeze at 1 Point 6 54 degree celcius 0 654 degree celcius

2 experimental method to calculate order and rate law of eaction and methods to monitor the progress of reaction 26 Formation of NO F from NO and F as per the reaction 2NO g F g 2NO F g is a second order reaction first order with respect to NO and first order with respect to F If NO and F are present in a closed vessel in ratio 2 1 maintained at a constant temperature with an initial total pressure of 3 atm what will be the total pressure in the vessel after the reaction is complete 1 latm 3 2 5 atm 2 2 atm 4 3 atm

3 For a given reaction energy of activation for forward reaction E is 80 kJmol 1 AH 40 kJmol 1 for the reaction A catalyst lowers E by 20 kJ mol 1 The ratio of energy of activation for reverse reaction before and after addition of catalyst is 1 1 0 3 1 2 2 0 5 4 2 0

Knowing that the chemistry of lanthanoids Ln is dominated by its 3 oxidation state which of the following statements is incorrect The ionic sizes of Ln III decrease in general with increasing atomic number Ln III compounds are generally colourless Ln III hydroxides are mainly basic in character Because of the large size of the Ln III ions the bonding in its compounds is predominantly ionic in character

Consider the reaction 2A B Product When concentration of B alone was doubled the rate of reaction increased by two times and when the concentration of both A and B were doubled the rate became 4 times The unit of rate constant for this reaction is 1 L mol 1 S 1 3 mol L 1 s 1 2 Unitless 4 S 1

4 8 g of oxygen is adsorbed on 1 2 g of metal powder The volume of oxygen adsorbed per gram of the adsorbent at NTP is NCERT Pg 124 1 2 8 L 3 4 6 L 2 3 6 L 4 3 21

2 33 Calculate the work involved when 1 mol of an ideal gas is compressed reversibly from 1 00 bar to 5 00 bar at a constant temperature of 300 K 1 14 01 kJ 3 4 01 kJ 2 18 02 kJ 4 8 02 kJ

A compressor is an important device used in industrial plants Most industrial plants have used the compressor to supply air to the reactor or combustion unit i Explain the main function of a compressor 1 Marks

In context with the transition elements which of the following statements is incorrect In the highest oxidation states the transition metals show basic character and form cationic complexes In the highest oxidation states of the first five transition elements Sc to Mn all the 4s and 3d electrons are used for bonding Once the configuration is exceeded O the tendency to involve all the 3d electrons in bonding decreases In addition to the normal oxidation states the zero oxidation state is also shown by these elements in complexes

A light source of frequency 6 x 1015 Hz is subjected to a metal sheet having work function equal to 22 6 eV Then the velocity of photo electrons emitted having maximum kinetic energy will be Planck constant h 6 626 x 10 34 J s 1 4 43 x 105 m s 2 3 21 x 107 m s 3 8 89 x 105 m s 4 8 73 x 106 m s

Let the mass of electron is two times mass o proton is 1 4th and mass of neutron is 3 2 a original mass Then the atomic weight of C atom 1 Increases by 37 5 2 Decreases by 87 5 3 Decreases by 12 5 4 Remains same

ostion No 32 40 The mechanism of the decomposition of ethane is given as C H2CH CH C H6 CH4 C H C H C H4 H H C H6 H C H H C H C H6 For which of the following species steady state approximation can be app AO C H BOC H6 COC H CHA

number for cations and anions in the packed structure will be same 1 Point Chloride ion forms fcc lattice and sodium ions occupy all octahederal voids of the unit cell Calcium ions form fcc lattice and fluoride Oions occupy all the eight tetrahederal voids of the unit cell Oxide ions form fcc lattice and sodium ions occupy all the eight tetrahederal voids of the unit cell Sulphide ions form fcc lattice and zinc ions go into alternate tetrahederal voids of the unit cell

Liquid C dissolves completely in water The vapour pressures at 20 C of an aqueou solution of C mol fraction 0 28 liquid C and water are 26 0 mmHg 43 5 mmHg ar 17 5 mmHg respectively Prove the aqueous solution C behaves as a non ide solution

7 Which of the following statements are not true 1 Point Vacancy defect results in a decrease in the density of the substance Interstitial defect results in an increase in the density of the substance Impurity defect has no effect on the density of the substance Frenkel defect results in an increase in the density of the substance

8 An excess of potassium ions makes KCI crystals appear violet or lilac in colour since 1 Point Some of the anionic sites are not occupied by unpaired electrons Some of the anionic sites are occupied by a pair of electrons There are vacancies at some anionic sites F centres are created which impart colour to the crystals

Q 51 The spectral lines of atomic hydrogen wave number is equal to the difference between the wave numbers of the following two lines of the Balmer series 486 1 and loid 410 2 nm The wavelength of that line is 10 4 cm

The standard enthalpies of formation of H O 1 and CO g are respectively 286 kJ mol and 394 kJ mol If the standard heat of combustion of CH4 g is 891 kJ mol then the standard enthalpy of formation of CH4 g is A 75 kJ mol B 75 kJ mol C 211 kJ mol D 211 kJ mol E 1571 kJ mol

where dr is a small volume element The values of y which are in accordance with the above conditions are taken as valid and are known as Eigen functions and the values of E corresponding to valid values of u are called Eigen values The eigen function for an electron is called an atomic orbital Note As the eigen values are very nearly similar to energy levels of different Bohr s orbits the occurrence of definite energy levels in an atom follows directly from the wave mechanical concepts Significance of y The wave function may be regarded as the amplitude function expressed in terms of coordinates x y and z The wave function may have positive or negative

Although nitrogen does not adsorb on surface at room temperature it adsorbs on surface at 83K Which one of the following statements is correct Question Type Single Correct Type 1 2 3 4 At 83K there is formation of monomolecular layer At 83K there is formation of multimolecular layer At 83K nitrogen molecules are held by chemical bonds At 83K nitrogen is adsobed as atoms

2 53 For a reaction Ag nB the rate constant is 6 93 x 10 sec The reaction is performed at 8 constantpressure and temperature of24 63 atm and 300 K starting with 1 mole of pure A 3 M 3 25 H If concentration of B after 2000 sec is then the value of n is

increase with dilution 58 For a dilute solution of a strong electrolyte the variation of molar conductivity with concentration is given by 2 A A m Ac 1 Am Am Ac A 3 A A A C m 4 A A m A C

Construct the expression for Kc for the following reaction FeO s H g Fe s H O g 1 Drag the tiles into the numerator or denominator to form the expression Kc

6 The values of Aeq for NH4C1 NaOH and NaCl are respectively 149 74 248 1 and 126 4 ohm cm eq The value of ANH OH is eq 1 371 44 2 271 44 V 3 71 44 4 It cannot be calculated from the data given

The separation of components in a distillation column is based on the differences in volatility and boiling point As the vapor rises the tower and contacts the liquid i Why do you think reflux is needed in a distillation column 2 Marks

0 001x107 A certain substance A is mixed with an equimolar quantity of substance B At the end of an hour A is 75 reacted Calculate the time when A is 10 unreacted Given order of reaction is zero A B 75x t anirs 17 1

The surface of copper gets tarnished by the formation of copper oxide N2 gas was passed to prevent the oxide formation during heating of copper at 1250 K However the N gas contains 1 mole of water vapour as impurity The water vapour oxidises copper as per the reaction given In PH PM 0 below 2Cu s H O g Cu O s H g PH is the minimum partial pressure of H in bar needed to prevent the oxidation at 1250 K The value of In PH is Given total pressure 1 bar R universal gas constant 8 J K 1 mol In 10 2 3 Cu s and Cu O s are mutually immiscible At 1250 K 2Cu s 2O2 g Cu O s AG 78 000 J mol 1 H2 g O2 g H O g AGe 1 78 000 J mol G is the Gibbs energy 2018

On the basis of de Broglie equation the following conclusions can be drawn 1 Lighter the particle greater is its de Broglie wavelength for certain velocity ii Faster the particle moves smaller is its de Broglie wavelength iii The de Broglie wavelength is independent of the nature of the particle iv The de Broglie equation is applicable to microscopic particles such as electron proton atom molecule etc and has no significance for heavier particles The wavelength is too small in the case of heavier particles which is difficult to measure Let us apply the equation to a moving electron and a moving ball weighing 200 g or 0 2 kg both travelling with the same speed 106 m s For electron 34

x 100 J of energy was supplied to a system in an isothermal manner at constant pressure What is the work done during 8 a the process nobl a W 0 c W 100 J qete gninimatab 10 b A d W 200 J MOTOR

18 In an ionic compound A B the radii of A and B are 1 0pm and 2 0pm respectively The volume of the unit cell of the crystal AB will be 1 Point 27 pm cube 64pm cube 125 pm cube

The solubility of a salt of weak acid AB at pH 3 is Yx 10 mol L 1 The value of Y is Given that the value of solubility product of AB Ksp 2 10 10 and the value of ionization constant of HB K 1 10 8 4

acetic acid and treated with excess KI The liberate requires 11 3 mL of 0 05 M Na S O3 solution for c reduction Find out the mole ratio of Cu and C the compound Write the balanced redox reactions in the above titrations IIT JEE A 1 0 g sample of Fe O3 solid of 55 2 purity is d in acid and reduced by heating the solution with z The resultant solution is cooled and made upto 10 An aliquot of 25 0 mL of this solution requires 17 0 0167 M solution of an oxidant for titration Calc number of electrons taken up by the oxidant in the of the above titration IIT JE A 2 0 g sample of a mixture containing sodium c sodium bicarbonate and sodium sulphate is gent T