Physical Chemistry Questions

When 1 mol of A g is introduced in a closed rigid 1 litre vessel maintained at constant temperature the following equilibria are established A g B g C g C g D g B g The pressure K K at equilibrium is twice the initial pressure Calculate the value of if

For the reaction A g B g at 495 K A Go 9 478 kJ mol 1 If we start the reaction in a closed container at 495 K with 22 millimoles of A the amount of B is the equilibrium mixture is millimoles Round off to the Nearest Integer R 8 314 J mol 1 K 1 ln 10 2 3031

Which of the following will show Tyndall effect 1 Aqueous solution of soap below critical micelle concentration 2 Aqueous solution of soap above critical micelle concentration 3 Aqueous solution of sodium chloride 4 Aqueous solution of sugar

llustration 17 3 2 g of pyrolusite was treated with 50 mL of 0 5 M oxalic acid and some sulphuric acid The ox acid left undecomposed was raised to 250 mL in a flask 25 mL of this solution when treated 0 02 M KMnO4 required 32 mL of the solution Find the of MnO in the sample and also percentage of available oxygen plution

C s O g CO g 94 2 Kcal H g O g CH g 20 g The heat of formation 1 45 9 2 47 8 3 209 72 H O 1 68 3 Kcal CO g 2H O 21 08 of methane in Kcal will be

Question 5 K Cr2O7 can supply oxygen to oxidise pollutants in a water sample If one kilogram of such water sample requires 20 ml of 0 1 MK Cr2O7 H what is the oxygen requirement of that water in ppm units Options a 96 ppm b 48 ppm c 24 ppm d 32 ppm

Q7 A homogeneous gas reaction A 3R has a reported rate at 215 C A 10 2C5 mol liter sec Find the space time needed for 80 conversion of a 50 A 50 inert feed to a plug flow reactor operating at 215 C and 5 atm CAO 0 0625 mol liter 24

Which among the following pairs of Vitamins is stored in our body relatively for longer duration 1 Thiamine and Vitamin A 2 Vitamin A and Vitamin D 3 Thiamine and Ascorbic acid 4 Ascorbic acid and Vitamin D

7 Which transition emits photon of maximum frequenc 1 2nd spectral line of Balmer series 2 2nd spectral line of Paschen series 3 5th spectral line of Humphery series 4 Ist spectral line of Lymen series

yind massless piston assembly in which ideal gas is filled Cross sectional area of the cylinder 1m Three masses m m and m3 are kept on the piston When m is removed piston moves upto point A When m1 and m both are removed piston moves upto point B and when m m and M3 all the three are removed piston moves upto point C The work done by the gas is when piston moves from point B to point C Given m 2 x 10 kg m 3 x 10 kg 8 10 m s 2 P 105 Pa atm m m m3 in dng P 106 Pa B FA 20

3 Ans E ans Why do hydrocarbon molecules with an odd number of carbons atoms have lower melting points than those with an even number of carbon atoms Identify the structure of A and B CH3 CH COOH Wbu de KOH A Kolbe s electrolysis B bonds rather than C H bonds break during cracking of alkanes

B CH CH CH II CH CH CH 1 III Which of following orders is correct for heat of hydrogenatio of these compounds 1 I II III 2 III II I 3 II III I

5 1 M solution of monobasic acid HX has molar conductivity x Scm mol while molar conductivity of H and X at infinite dilution is 300 Scm mol and 100 Scm mol respectively The 1 M HX solution contains 0 15 M H If this 1 M solution is filled in a conductivity cell of cell constant 0 1 cm the conductance is found to be Y ohm 1 The value of 10Y is

Describe the motion of a charged particle in uniform magnetic field In a chamber a uniform magnetic field of 6 5G is maintained An electron is shot into the field with a speed of 4 8x106ms normal to the field Determine the radius of the circular orbit e 1 6x10 C M 9 1x10 Kg

A fermentation experiment was conducted to study the production of ethanol using a new strain of Saccharomyces spp Based on the data in Table 1 determine the kinetic for ethanol production with Leudeking Piret equation 15 marks Table 1 Time h 0 123456 2 Dry biomass Glucose g L g L 0 2 0 6 2 1 2 8 4 5 9 6 2 180 150 125 98 83 24 8 Ethanol concentration g L 0 0 8 16 35 60 78 dX dt 0 0 4 1 0 1 5 1 7 1 2 0 4 dP dt 0 0 7 9 16 28 23

Quinhydrone is a sparingly soluble one to one addition compound formed from hydroquinone and quinone When solid quinhydrone is dissolved in an aqueous medium equal concentrations of hydroquinone and quinone result If a platinum wire is dipped into the solution the potential of the electrode is governed by the reversible reaction 2H 2e OH OH H Q Where Q denotes quinone and H Q denotes hydroquinone The E value of this half cell reaction is 0 46V with respect to the saturated calomel reference electrode SCE Because the potential of the quinine hydroquinone half reaction depends on the concentration of hydrogen ion it is possible to use this system to measure pH A sample solution of unknown pH was saturated with quinohydrone and a platinum electrode was dipped into it If the potential of the such electrode was found to be 0 22V with respect to SCE what was the PH of the sample solution 2 303 RT Given 0 06 F

32 Calculate the cell emf in mV for pt H 1 atm HC1 0 01 M AgCl s Ag s at 298 K if AG values at 25 C are 109 56 KJ mole for AgCl and 130 79 KJ mole OSR IIT CO SC Page No

4 glucose and galactose in equimolar amounts 4 si T 141 40 mL sample of 0 1 M solution of nitric acid is added to 20 141 40 mL 0 1 M 20 mL 0 3 Malf fac mL of 0 3 M aqueous ammonia What is the pH of the face pH resulting soution pKb of NH OH 4 74 1 5 05 2 9 95 3 8 95 4 8 56 NH OH pk 4 74 1 5 05 2 9 95 3 8 95 4 8 56

Calculate the wavelength in nanometer associated with a 73 proton moving at 1 0x10 ms Mass of proton 1 67x10 27 1 0 40 nm 2 2 5 nm 3 14 0 nm kg and h 6 63 x 10 Js C

Unit cell of a metal has edge length of 288 pm and density of 7 86 g cm Determine the type crystal lattice Atomic mass of metal 56 g mol Define instantaneous rate of reaction Explain pseudo first order reaction with suitable example

Study the following figure and choose the correct options Assuming complete dissociation of electrolyte 0 05 M aq Al2 SO4 3 solution SPM 0 10 Maq MgCl solution a There will be no net moment of any substance across the membrane b MgCl will flow towards the Al2 SO4 3 solution c Al SO4 3 will flow towards the MgCl solution d The osmotic pressure of 0 1 M MgCl is higher than the of 0 05 M Al SO4 3

0 3 Marks Calculate partial pressure of O2 if the density of a mixture of O2 and N is 1 3 gL at STP 1 A B O D 0 5 0 25 0 42 0 28 6 150 Explanation EASY

Which statement is true for solution of 0 020 M H SO4 2 a 2 litre of the solution contains 0 020 mole of SO b 2 litre of the solution contains 0 080 mole of H30 c 1 litre of the solution contains 0 020 mole H30 d None of these

If 10 dm of water is introduced into a 1 0 dm flask at 300 K how many moles of water are in the vapour phase when equilibrium is established Given Vapour pressure of H O at 300 K is 3170 Pa R 8 314 JK mol a 5 56 10 mol c 4 46 10 2 mol b 1 53 x 10 2 mol d 1 27 10 3 mol

Metal M is the most abundant metal in the Earth crust Its electronic configurat ion is 2 8 3 and occurs in the Earth cru st as its oxides M203 Name the ore of t he metel containing M203 Explain the method used for concentration of the o re Also give reason for choosing that method

Q 55 If the value of Ksp for Hg Cl s is X then the value of X will be where pX log X Given Hg Cl s 2e 2Hg 1 2Cl 2 Hg 2e 2Hg 1 E 0 27 V E 0 81 V

of 0 01 M MgCl is 220 S cm mol of MgCl is 240 S cm mol 2 of Mg is 100 S cm mol All above measurements are done in an conductivity cell Assuming MgCl to be a strong electrolyte which of the following is incorre A Limiting equivalent conductivity of MgCl is 480 S cm eq B of MgCl varies linearly with its concentration C of 0 04 M MgCl will be 160 S cm mol D 2 of 0 04 M MgCl will be 200 S cm mol A

Determine the order of reaction its rate const The half life period of decomposition of a compound is 50 minutes If the initial concentrat the half life period is reduced to 25 minutes What is the order of reaction

Consider the following acid catalysed reaction A H B Rate R K H At pH 3 time to reduce the concentration of A from 5 M to 3 5 M is 60 minutes Which of the following statement s is are true 1 The value of K is 25 min The value of K is 25 M min The value of K is 50 M min Half life of the reaction is 100 min

50 75 For the redox reaction Zn s Cu 0 1M 2 1M Cu s taking place in a cell E is 1 10 Volt E for the cell will be 010591 1 1 80 volt 2 1 07 volt 40 Ne 3 0 82 voit 4 2 14 volt

The self ionization constant for pure formic acid K HCOOH HCOO has been estimated as 10 4 at room temperature What percentage of formic acid molecules in pure formic acid is converted to formate ion Given d H 1 22 g cc 1 0 0185 2 0 0073 3 0 074 4 0 037

4 6 02 10 4 6 02 x 10 63 An alkyl bromide X reacts with Na to form 4 5 63 X fear fa diethyloctane Compound X is Ext 1 CH CH Br 2 CH CH Br 3 CH CHL CH Br CH 1 CH CH Br 2 CH CH Br 3 CH CH CH Br CH 4 CH CH CH Br CH CH 64 Which will dehydrate easily 4 CH CH CH Br CH CH 64 faran facicera sar

13 Following is the composition of a washing soda sample Substance Molecular Wt Mass percent Na CO3 NaHCO3 NaCl 106 0 84 0 58 5 a 9 mol of CO c 17 mol of CO On complete reaction with excess HC1 one kilogram of the washing soda will evolve 84 8 8 4 6 8 b 16 mol of CO d 18 mol of CO

Given below are two statements Statement I Both CaCl2 6H O and MgCl 8H O undergo dehydration on heating Statement II BeO is amphoteric whereas the oxides of other elements in the same group are acidic In the light of the above statements choose the correct answer from the options given below 1 Statement I is false but statement II is true 2 Both statement I and statement II are false 3 Both statement I and statement II are true

The reaction CO Cl K K CI CO Cl Column I Q1 d COCI dt Q2 COCI Q3 COCI Cl COCl Cl slow Match the terms given in Column I with their correct expression given in Column II Q4 K 2CI fast K K4 A1 COCI fast K COCI follows the mechanism A2 A3 A4 A5 Column II A1 Ks COCI C1 A2 A3 1 2 K3 K CO C1 12 K K A4 A5 CI CL Ks COCI CO C K3 K K K 1 2 co C1 2

By how much times will potential of half cell Cu Cu change if the solution is diluted 100 times at 298 K A Increases by 59 mV B Decrease by 59 mV 42 C Increases by 29 5 mV 70 71 D Decreases by 29 5 mV

0 5 mole of electron is passed through two electrolytic cells in series One contains silver ions and the other zinc ions Assume that only cathode reaction in each cell is the reduction of the ion to the metal How many gm of each metals will be deposited

The same amount of electricity was passed through two separate electrolytic cells containing solution of nickel nitrate Ni NO Jand chromium nitrate Cr NO respectively If 0 3 g of nickel was deposite in the first cell the amount of chromium deposited is kohlaw law at wt of Ni 59 at wt of Cr 52 A 0 1 g B 0 17 g C 0 3 g D 0 6 g

Which of the following represents the reduction potential of silver wire dipped into 0 1 M AgNO solution 0 0351 toy Ag Cau tieu at 25 C e Ag Ay 1 D E A E red B E 0 059 red C E OXI 0 059 red 0 059 3

4 Thiosulphate ions upon reaction with AgNO give white precipitate which gradually changes to black upon hydrolysis the sum of the oxidation state of sulphur in the products obtained after hydrolysis is

The mass of a dust particle is 10 2 g and its velocity is 104 cm sec The error in the measurement of velocity is 0 01 The uncertainty in the measurement of h position in unit is 4T 0 527 x 10 2 27 ergsec

5 State Ampere s curcuital law A 3 cm wire carrying a current of 10A is placed inside a solenoid perpendicular to its axis The magnetic field inside the solenoid is given to be 0 27T What is the magnetic force on the wire 3

entify the true statement s among the following A B C D 2 for a strong electrolyte in water m decreases as the electrolyte concentration increases At low concentrations conductivity for a strong electrolyte in water increases as the electrolyte concentration increases Conductivity for a strong electrolyte in water always increases as the electrolyte concentration increases for a weak acid HX 200 200 YOU M YOU M YOU M YOU M

Which of the following will increase the voltage of the cell with following cell reaction Sn 2Ag Sn 2 2Ag s aq A Decrease in the concentration of Ag ions B Increase in the concentration of Sn 2 ions C Increase in the concentration of Ag ions D A B both

interconnecting them through In two vessels each containing 500ml water 0 5m mol of aniline K 10 9 and 50mmol of HCI are added separately Two hydrogen electrodes are constructed using these solutions Calculate the emf of cell made by connecting them appropriately of the following cell

46 The following facts are available 2A B 2B A No reaction 2C B 2D A 2A D Which of the following statement is correct 1 EO C C 2 EC IC C C 3 E E B B2 E B B E B B E ATA E E E E A A ATIA D D D D E DVD

1 2 3 4 t3 4 11 2 17 8 11 2 17 8 11 2 t15 16 3 first order reaction der 3 second order reaction 7 4 zero order reaction A 15 first order reaction

46 A mixture of CO and CO has vapour density 20 at STP 1 46 COCC kg of this mixture would contain 1 3 75 mole CO 2 6 25 mole CO 3 2 mole CO 4 4 mole CO fast fa 1 3 75 2 6 25 3 2 MALAY

The reduction potential values are given below Al Al 1 67 volt Mg2 Mg 2 34 volt Cu Cu 0 34 volt Which one is the best reducing agent A AI B Mg 1 21 0 53 volt C Cu

40 mmol R NH OH undergoes an electrolytic oxidation by 8 A current for 965 sec with 50 current efficiency as R NH OH H O R NO H e The process is done in 100 mL buffer solution made by 0 8 M Na HPO4 and 0 2 M Na3PO4 then find the value of x if x is pH of buffer after electrolysis For H PO4 PK 2 pka 7 pka3 pKaz 7 6 9 2 5 6 12