Physical Chemistry Questions

Which statement about standard reduction potentials is correct a E b E H H c A redox reaction is feasible if sum of SRP of oxidant and that of reductant is a positive quantity d K Cr O acid is stronger oxidising agent than KMnO acid 0 you D D 0 10

3 For the allotropic change represented by the equation C graphite C diamond the enthalpy change AH 1 9 kJ If 6 g of diamond and 6 g of graphite are separately burnt to yield CO the heat liberated in first case is a less than in the second case by 1 9 kJ Vogrine s MISTURIN b more than in second case by 11 4 kJ Insa takto pie Oct c more than in the second case by 0 95 kJ EL CURST d less than in the second case by 11 4 kJ Consbl BIA 6

A variable opposite external potential Eext is applied to the cell Zn Zn 1 M Cu2 1 M Cu of potential 1 1 V When Eext 1 1 V and Eext 1 1 V respectively electrons flow from 1 anode to cathode and cathode to anode S 2 cathode to anode and anode to cathode 3 cathode to anode in both cases anode to cathode in both cases 4

The radius of the second Bohr orbit for hydrogen atom is Planck s Constant h 6 6262x10 34 Js mass of electron 9 1091x10 31kg charge of electron e 1 60210 10 19 C permittivity of vacuum 2017 A 8 854185 10 2kg m A 2 12 B 1 65 C 4 76 D 0 529

The heats of combustion of hydrogen car bon monoxide and methane are 285 284 and 890 kJ mor The calorific value is maximum for a H b CO c CH d Cannot be redicted as information is incomplete

3 0 molal NaOH solution has a density of 1 110g mL The molarity of the solution is a 29732 b 3 05 a 3 0504

6 The reaction H S H O2 S 2H C manifests 1 Oxidising action of H O 2 Reducing nature of H O 3 Acidic nature of H O 2 4 Alkaline nature of H O

3 For a reaction 2N O 4NO O i 5 5 Initial concentration of N O is 7 2 mol L and after 20 minute NO 2 4 mol L then what will be of N O5 in K in A rate of decomposition Inmol L min Fr 2 1 1 0 06 2 0 03 3 1 3 4 2 4 5 PRO FRA

A balloon blown up with 1 mole of gas has a volume of 480 mL at 5 C The balloon is filled to 7 8 th of ins maximum capacity Suggest a Will the balloon burst at 30 C b The minimum temperature at which it will burst c The pressure of gas inside the balloon at 5 C d The pressure of gas when balloon bursts

The oxidation state shown by silicon when combines with strong electropositive metal is 1 2 2 4 3 4 4 2

benzene and toluene 4 water and HCI On mixing 10 mL of acetone with 40 ml of chloroform the total volume of the solution is 1 50 mL 2 50 mL 3 50 mL The mixture of n hexane and n heptane is an even 4 cannot be predicted

The degree of hydrolysis of a salt of weak acid HA and weak base BOH in its 0 1 M solution is found to be 10 If the molarity of the solution is 0 05 M the percentage hydrolysis of the salt should be offolod zwoller 2 10 1 5 3 20 4 None

The equilibrium constant K for the reaction 2NOCI g 2NO g Cl g is 6 95 x 108 at 298 K The standard Gibb s free energy change AG at 298 K will be R 2 cal K 1 mole log 6 95 0 8420 1 4 912 kcal 3 7 3 kcal 2 14 74 kcal 4 9 825 kcal

4 w at isothermal AIPMT 2014 For the reaction X O4 l 2XO2 g AU 2 1 kCal AS 20 cal K at 300 K Hence AG is 1 2 7 kCal 3 9 3 kCal 2 2 7 kCal 4 9 3 kCal AIIMS 2014

37 For the reaction X O4 l 2XO g AU 2 1 kCal AS 20 cal K 1 at 300 K Hence AG is 1 2 7 kCal 3 9 3 kCal 2 2 7 kCal 4 9 3 kCal

Given E Cr 0 74 V E AMA 1 51 V MnO4 Mn2 E Cn0 Cr3 1 33 V E 1 36 V CI CI 3213 Based on the data given above strongest oxidising agent will be 1 CI 2 Cr 3 Mn2 4 M

The sum of the number of lone pairs of electrons on each central atom in the following s is JEE Adv TeBr BrF SNF and XeF3 Atomic number N 7 F 9 S 16 Br 35 Te 52 Xe 54

40 Agcl can be obtained a by extraplotation of the graph A and C to zero concentration b by known values of A of AgNO3 HCl and HNO 3 c both a and b d None of these

E value for the cell reaction Cu l Cu 0 001 M Cu 0 1 1 In 0 01 3 RT F RT F In 0 01 2 4 RT F RT F M Cu is In 0 1 In 0 1

0 441V and E3 Fe 2 0 771V the standard EMF of the reaction Fe 2Fe 3 3Fe 2 will be 1 0 330 V 2 1 653 V 3 1 212 V 4 0 111 V If E Fe 2 Fe

If the energy absorbed by each X molecule of a gas is 3 5 x 10 19 J and the bond energy of X is 180 6 kJ mol 1 then the kinetic energy per atom will be 1 2 5 x 10 19 J 3 2 5 x 10 20 J 2 5 0 10 20 J 4 1 5 10 19 J Office A

9 An alloy of Pb Ag weighing 1 08 g was dissolved in dilute HNO and the volume made to 100 mL A silver electrode was dipped in the solution and the emf of the cell set up as Pt s H g H 1M Ag aq Ag s was 0 62 V If E is 0 80 V what is the percentage of Ag in the alloy At 25 C RT F 0 06 A 25 0 10 B 2 50 D 50

9 57 The rapid change of pH near the stoichiometric point of an acid base titration is the basis of indicator detection pH of the solution is related to ratio of the concentrations of the conjugate acid HIn and base In forms of the indicator by the expression A log C log Hin In In Hin pK pH In pH pK In B log D log Hin In In Hin pH pK In pK pH In

The gold number of gelatin is 0 01 Calculate the amount of gelatin in mg to be added to 1000 mL of a colloidal sol of gold to prevent its coagulation before adding 1 mL of 10 NaCl solution

20 The angular momentum of an electron in a Bohr s orbit of H atom is 42178x10 34 kg m sec wavelength ing Calculate the spectral life emitted when electron falls from this level to next lower level

How many electrons in an atom have the following quantum numbers n 4 m 1 2 b 18 a 32 c 8 d 16

4 100 cm of 1 M CH3COOH was mixed with 100 c 2M CH3OH to form an ester The change in the initial rate each solution is diluted with equal volume of water would be KCET 2015 a 0 5 times c 0 25 times b 2 times d 4 times

2 If equal quantities of electricity are passed through three voltameter containing FeSO4 Fe SO4 3 and Fe NO3 3 then which of the following is not true 1 Amount of iron deposited in FeSO4 and Fe SO4 3 is equal 2 Amount of iron deposited in Fe NO3 3 is 2 of the amount of iron deposited in FeSO4 3 Amount of iron deposited in Fe SO4 3 and Fe NO3 3 are equal 4 Same gas will evolve in all three cases at

Two moles of ammonia is introduced in a evacuated 500 ml vessel at high temperature The decomposition reaction is N g 311 g 2NI 1 g N g At the equilibrium NI I becomes 1 mole then the K would be 1 0 42 3 1 7 d 2 6 75 4 1 5

5 Dal lake has water 8 2 x 10 2 L approximately A power reactor produces electricity at the rate 1 5 x 10 Cs at an appropriate voltage How many years would it take to elec trolyze the lake A 2 4 million years C 1 8 million years B 5 3 million years D 4 6 million years

Which of the following cations is not hydrolyzed in aqueous solution ii Ca iii Na 3 i ii iii iv i Mg2 1 i ii 2 iii iv 11 iv K 4 i ii iii

3 The behaviour of a real gas is usually depicted plotting compressibility factor Z versus P at a consta temperature At high temperature and high pressur Z is usually more than one This fact can be explain by van der Waals equation when a The constant a is negligible and not b b The constant b is negligible and not a c Both the constants a and bare negligible d Roth

In an experiment addition of 4 0 mL of 0 005 M BaCl to 16 0 mL of arsenious sulphide sol just causes the complete coagulation in 2 h The flocculating value of the effective ion is

7 One litre of a mixture containing BaF2 and H SO4 was taken for analysis 25 mL of this mixture was treated with 20 0 mL of 0 1N KOH for complete neutralisation Another 25 mL of the mixture was added to 100 mL of 0 05 N K CO3 solution and precipitate was filtered off The filtrate required 12 mL of 0 025 M oxalic acid solution using phenolphthalein as indicator Find the strength of BaF and HSO in mixtura

3 Pressure of the gas in column 1 is A 60 cm of Hg 60 B 55 cm of Hg 20 cmp 6 8 g ml of liquid x 20 cm Hg P 75 of Hg C 50 cm of Hg D 45 cm of Hg

A Which of the following options are correct Cast iron is obtained by remelting pig iron with scrap iron and coke using hot air blast In extraction of silver silver is extracted as cationic complex Nickel is purified by zone refining Zr and Ti are purified by van Arkel method B C D

Electrode potential of the half cell Pt s Hg 1 Hg Cl s Cl aq can be increased by b Decreasing Cl d Decreasing Hg 1 30 a Increasing Cl c Increasing Hg Cl s The equilibrium co on stant fon for th foll

E Mg2 Mg 2 37V E Ag Ag 0 8 V Calculate E and E for the cell Sn Sn 1M Pb 10 M Pb E Sn Sn 0 14V E Pb Pb 0 13V Is cell representation is correct Cult in a solution of CuSO will the electrode potential be zero at 25 C

Density of 2 05 M solution of acetic acid in water is 1 02 g mL The molality of same solution is a 1 14 mol kg c 2 28 mol kg 1 AIEEE 2006 b 3 28 mol kg d 0 44 mol kg 1

59 10 mole of SO2 and 15 mole of O2 were passed over catalyst to produce 8 mole of SO3 The ratio of SO 2 and SO 3 moles in mixture is a 5 4 b 1 4 c 1 2 d 3 4

5 What is the OH in the final solution prepared by mixing 20 0 mL of 0 050 M HCl with 30 0 mL of 0 10 M Ba OH a 0 10 M c 0 0050 M b 0 40 M d 0 12 M

8 Light of wavelength 300 x 10 m strikes a ma surface with photoelectric work function of 2 13 Find out the kinetic energy of the most energ photoelectron

EMF of Daniell cell was found using different concentrations of Zn ion and Cu2 ion A graph Zn Cu The plot was found to be linear with intercept on axis equal to 1 10 V Ecell for Zn Zn 0 1M Cu2 0 01M Cu will be 1 1 10 V 3 0 93 V was then plotted between Eell and log Ecell 2 1 0705 V 4 0 078 V

When CO is dissolved in water following equilibrium is established CO 2H O H O HCO3 for which equilibrium constant is 3 8 10 7 and pH 6 0 The ratio HCO3 CO would be 1 3 8 10 13 X 2 3 8 10 1 3 6 0 4 13 4 16

4 412 H S 4H O 9 A drop 0 05 mL of 12M HCl is spread over a thin sheet of aluminium foil thickness 0 10 mm and density of Al 2 70g mL Assuming whole of the HCl is used to dissolve Al what will be the maximum area of hole produced in foil

Back bonding plays a central role in the following phenomena B X bond length is lower in BF3 as compared to BC13 Stronger acidic strength of CH3 3SiOH as compared to CH3 3COH Less lewis basic strength of SiH3 3N as compared to CH3 3N Less stability of Si Si X as compared to

45 Study the table carefully and select the appropriate options Sample Physical P Q R S State Solid of electricity X P 1 Aluminium 2 Phosphorus 3 Iron 4 Sulphur X Conductor Ductility Q CGraphite Nitrogen Zinc Copper X R Bromine Magnesium Tin Potassium X X X S Sodium Aluminium Fluorine Bromine

A pure radio chemical preparation was observed to disintegrate at the rate of 2140 counts minutes at 12 35 P M At 3 55 P M of the same day the disintegration rate of the sample was only 535 count minutes What is the half life of the material

2 How much of Fe can be theoretically obtained by the reduction of 1 kg of Fe O3 3 Calculate the mass of 60 H SO4 required to decompose 50 g of chalk calcium carbonate Which is chooner 40 hydrochloric acid at the rate of 50 paise per kilogram or 80 H SO a

Electron Affinity of Cl is 3 7 eV How much Energy released in kCal when 2g of gaseous chlorine atoms is converted to Cl ions in the gaseous state A 4 80 kCal Correct Answer 5 20 kCal 1 50 kCal MANSZAMAL water wwwww stop NYAMA