Physical Chemistry Questions

b Calculate the activation energy kJ mol and frequency factor for the reaction Express the final answers with 4 sig figs 5 pts en k 02331 4 605 Arrhenius Plot for Reaction A g 28 g AB 0 002907 0 003663 VT VK

In Kjeldahl s method of estimation of nitrogen in organic comp g of organic compound evolved ammonia which is neutralize by 20 ml of 0 2 M H SO4 Percentage of nitrogen in the organic compound is O 12 O 24 O 28 38

Two consecutive irreversible first order reactions can be represented by k k2 C k A B The rate equation for A is readily integrated to obtain A A o e kit and B 1 At what time will B be present in maximum concentration a k 1 1 k k k k k k k 2 When k 1s and k 500 s select most appropriate graph Conc a nga sh c Conc 3001 2005 t sec B b C t A C B In c b k A o e kit ek k k 4 Select the correct statement for given reaction Conc Conc c graph C In k k B t sec LAKE t sec t sec 3 If k and k both are almost same then which graph is most suitable a graph A b graph B B C t a A decreases linearly b B rises to a max and then constant c B rises to a max and then falls d The slowest rate of increases of C occuring where B is max d None of these C t A A d graph D

Following process is used in welding metals C H g O g H O g 2CO g 5 2 If 39 gm of acetylene undergo combustion at 25 Take R JK mol 3 A q for process 1197 5 kJ C AS 3000 J K 4H 1200 kJ mol 1 atm and 327 C then B Work done 2 5 kJ D AS is negative

ALLE Which of the following compound on reaction 83 with excess of AgNO forms three moles of precipitate white 1 PtC1 6NH 3 PtC1 5NH 2 PtCl4 4NH 4 PtC1 3NH An AgNO fal 1 PtC1 6NH 3 PtCl SNH 2 PtCl 4NH 4 DIGI ONEL

When a mole of photons of wavelength 5000A incident of lodine molecules present in 1Lt container it shows pressure of 8 21 atm at 300K then calculate kinetic energy of particles present in KJ given bond NA 6 x 1023 dissociation energy of iodine molecule is 45 6KJ per mole planks constant is 6 6X10 9

The rate of a chemical reaction doubles for every 10 C rise of temperature If the temperature is raised by 50 C the rate of the reaction increases by about AIEEE 2011 A B C D 64 times 10 times 24 times 32 times

2 9 10 M 3 1 8 10 M 4 3 6 10 M Which of the following order is not correct 1 CIO SO PO bond strength Reducing strength 2 SnCl PbCl 3 BeF BeF BeF s character 4 XeF XeO F dipole moment

How many mega joules of energy can on obtain from growing 2 375 acres of switchgrass over one year Assume that c can obtain 500 gallons of ethanol per acre switchgrass per year Group of answer choices 500 MJ 1 221 105 MJ 44 348 MJ

3 0 075 M sec If AHeaction for 2H O 1 196 kJ then find the AH 4 0 0083 M sec 3 0 075 M sec 4 0 0083 M sec 2H O A O g is 55 af ff 2H O 1 2H O O g of H O A AH H 196 kJ AH H O A reaction fer and farferl Given AH H O 188 kJ mol 1 286 kJ mol 3 494 kJ mol 2 143 kJ mol 4 98 kJ mol 1 286 kJ mol 3 494 kJ mol 2 143 kJ mol 4 98 kJ mol

5 C verfat will be for which enough gnug 25 The solubility product of CaSO4 2H O is 2 4 x 10 5 What mass of this salt will dissolve in 1 0 L of 0 0 SO4 of lone in

83 33 gm of 117 6 oleum is added to 1 litre of 3M K4 Fe CN 6 further 2 litre of 33 6 volume strength H O2 at 1 atm 273K is added to it resulting formation of K3Fe CN 6 K2SO4 water If final volume of the solution is 3 litre then select the correct statements s O H SO4 is limiting reagent 2 moles of K3Fe CN 6 is formed If 2 ml of resulting solution is heated then 37 3 ml of O at 1 atm 273K will be evolved from H O If 3 ml of resulting solution is heated then 37 3 ml of O at 1 atm 273K will be evolved from H O

ALLEN If IM of 2 5 L NaOH solution is mixed with 65 another 0 5 M of 3 L NaOH solution The molarity of resultant solution is 1 IM 2 0 727 M 3 0 86 M 4 0 50 M afe IM NaOH face 2 5 La 0 5 M NaOH facra 3L faren ard at font face F GKAI Brit 1 IM 3 0 86 M 2 0 727 M 4 0 50 M

The enthalpy of combustion of benzoic acid C6H5COOH is commonly used as the standard for calibrating constant volume bomb calorimeters its value has been accurately determined to be 3226 7 kJ mol When 3 2017 g of benzoic acid are burned in a calorimeter the temperature rises from 21 84 C to 26 67 C What is the heat capacity of the bomb Assume that the quantity of water surrounding the bomb is exactly 2250 g

vapour pressure at a given temperature Example 5 Vapour pressures of a liquid at 85 C and 96 C are 557 mm and 645 mm respectively Calcu molar heat of vapourisation of the liquid between 85 C and 96 C

Determine the mass of KOH if 46 3 of K3PO4 is produced and 92 8 of H3PO4 remains unreacted Atomic masses K 39 1 0 16 H 1 0 P 31 3KOH aq H3PO4 aq K3PO4 aq 3H20 e 367 g KOH 14 2 g KOH 36 7 g KOH you KOLU 2

54 AB g is dissociates as AB g AB g B g When the initial pressure of AB is 800 torr and the total pressure developed at equilibrium is 900 torr What fraction of AB g is dissociated 1 10 2 20 3 25 4 30 54 AB g fafara AB g AB g B g AB 4900 AB g fandall were fecifed gan 1 10 3 25 2 20 4 30

The activation energy for a reaction is 9 kcal mol The increase in rate constant when its temperature is increased from 298 K to 308 K is R 2 cal K mol 1 100 213 1 63 OPTIONS CLEAR SELECTION OA 75 OB 25 C 100 MARK FOR REVIEW

A vessel contains 1 mole of O at 27 C and 1 atm 51 27 C m A f ressure A certain amount of the gas was withdrawn and the vessel was heated to 227 C to 27 1 at for ren maintain the pressure of 1 atm The amount of as removed was 1 0 6 mole 3 0 5 mole 2 0 4 mole 4 0 1 mole 1 0 6 3 0 5 2 0 4 4 0 1

d 6 65 kJ mol The pyrolysis of an organic ester follows a first order process and its rate can be expressed as In K 78 09 42075 T Kalvin where K is given in the unit of min The time required for 25 percent reaction to complete at 227 C is a 50 mint b 125 mint c 250 mint d 500 mint

Which is correct statement about proton A proton is the nucleus of deuterium B proton is alpha particles C proton is ionized hydrogen molecules D proton is ionized hydrogen atom

Correct order of nucleophilicity for SN reaction 1 H H 0 CH COO 2 OH CH COO H O 3 H O CH COO OH 4 H O H CH COO

5 From the values of AH and AS predict which of the following reactions would be spontaneous at 25 C reaction A AH 10 5kJ mol AS 30J K mol reaction B AH 1 8kJ mol AS 113J K mol If either of the reaction is nonspontaneous at 25 C at what temperature might it become spontaneous

5 Compute the mass in grams of KCIO necessary to produce 67 2 litres of oxygen at S T P according 3 to the reaction 2KCIO3 s 2KCI s 30 g Molecular weight of KCIO3 122 5 1 96 2 2 3 122 5 4 245

A levo rotatory compound 2 chloro 2 pheny I butane is undergoing nucleophilic substitution with OH following SN1 mechanism The product s obtained is are a leavo rotatory 2 phenyl butan 2 ol b De xtro rotatory 2 phenyl butan 2 ol c 1 1 Mixture of both a and b d None o f these

Assertion A compound is made from sam e or different atoms combined in a fixed pro portion by mass Reason Constituents of compound exhibit their characteristics a Both assertion and reason are true and r eason is the correct explanation of assertio n b Both assertion and reason are true and reason is not correct explanation of asserti on c Assertion is true but reason is false d Both assertion and reason are false

where 2 303 RT F 0 0591 0 R 8 3147 T 273 K F 96500 C b R 8 314 J T 298 K F 96500 C c R 0 68212 atm T 273 K F 96500 C d R 0 0821 L atm T 298 K F 1 C

12 Select the correct statement s among the following a Mass by volume percentage unit is com monly used in medicine and pharmacy b Mass percentage concentration term is dependent on te mperature c In general a solute dissolve in a solvent if the Intermolecular interactions among mo lecules are much different in solutes and solvent d The solubility of a solid in a liquid in significan tly affected by temperature as well as by pressure 1 Only a and b 2 Only a and d 3 c 4 a c and d Answer given is 1 but how is b statement correct

16 What is the effect of the addition of sugar on the boiling and freezing points of water O a Both boiling and freezing points increase O b Both boiling and freezing points decrease c Boiling point decreases and freezing point increases d Boiling point increases and freezing point decreases

the initial For the reaction A B CD E reaction rate was measured for various initial concentrations of reactants The following data were collected Trial 23 A M 0 10 0 10 0 20 0 20 B C M M 0 10 0 10 0 10 0 30 0 10 0 10 0 10 0 20 Initial rate M s 3 0x10 5 9 0x10 1 2x104 1 2x10 4

44 Answer A SrCO3 s Addition of which of the following substance can increase the solubility of SrCO3 according to above reaction Rate this question NaCl B HCL Sr aq CO3 aq C K CO3

1 Select the correct statement s a Rate constants are never negative b Partial orders are never negative c Molecularity and order of reaction both are equal for elementary reactions d Order of reaction may be change with change in practical conditions temp and pressure 2 Select the correct statement s a The rate of reaction decreases with decrease in temperature b The rate of reaction is uniform in zero order reaction c The rate of reaction depends upon the surface area of the solid reactants d Average and instantaneous rate of reaction defined for micro and macro scopic time interval respectively 80 S 8 101 to nepomial to 06 d 8 0 i bloiy munoup OF 0

Balloons of 4L capacity are to be filled with Hydrogen at a pressure of 1 atm and 273 from an 8L cylinder containing Hydrogen 10 atm at the same temperature The nu ber of balloons that can be filled is 1 20 2 18 3 40 4 38

10 Write chemical equations for the following 1 Acid hydrolysis of Pentamide 2 Propanoic acid reacts with ammonia 3 Benzoic acid is treated with thionyl chloride 4 Hexanone on reaction with hydrazine

107 The half cell reduction potential of a hydrogen electrode at pH 10 will be 1 0 50 V 2 0 59 V 3 0 059 V 4 0 059 V 108 For a reaction M M ne A graph is plotted between reduction potential E and log M I

8 Assertion Haloalkanes react with KCN to form cyanoalkanes Reason KCN completely ionises in solution Both assertion and reason are correct Ostatements and reason is the correct explanation of the assertion 1 poir Both assertion and reason are correct O statements but reason is not the correct explanation of the assertion O O Assertion is correct but reason is wrong statement Assertion is wrong but reason is correct statement

46 t constant confirms the first order reaction If a t constant confirms that the order of reaction is a initial concentration of reactant 1 zero 2 first 3 second 4 third Which of following is correct formula for given polymer 47 46 47 a t a 1 3 fra

Three moles of an ideal gas at 200 K and 2 0 atm pressure undergo reversible adiabatic compression until the temperature becomes 250 K for the gas C is 27 5 JK mol in this temperature range 1 0 3 Calculate q w AU AH and final V and final P Given 1 4 2 1 5 4 13 3 2 61

Calculate the solubility in g L of Mn OH 2 in a 0 15 M aqueous solution of Mn Cl 2 aq The solubility product constant for Mn OH 2 1 90 10 13 M of Mn 54 94 g mol M of O is 16 00 g mol

What is the activation energy for a reaction if its rate doubles when the temperature is raised from 20 C to 35 C R 8 314 J mol K 1 342 kJ mol 1 2 269 kJ mol 1 3 34 7 kJ mol 1 4 15 1 kJ mol 1

At 80 C the vapour pressure of pure liquid A is 520 mmHg and that of pure liquid B is 1000 mmHg If a mixture of A and B boils at 80 C and 1 atm pressure the amount of A in the mixture is 1 25 mol 2 50 mol 4 48 mol ALLEN 57 3 34 mol An electron initially present in 80 C fer 1 25 3 34 en 520 mmHg 1000 mmHg 1 fe 2 50 4 48 A

Species Het Li Be 3 H He No of orbit radius in A Velocity of n of orbit electron m sec 2 1 587 4 36 x 10 Total energy of Pot Energy of Kinetic Energy electron eV electron eV of electron eV 6 8 3 4

Calculate the current in mA required to deposit 0 195 g of platinum metal in 5 0 hours from a solution of PICI atomic weight Pt 195 1 310 2 31 3 21 44 4 5 36 88 4 PtCl ungfer 45 0 0 195 for BIERGES BRI Pt 195 1 310 3 21 44 2 31 4 5 36

Why in the Geometry of BrF5 is the lone pair is in axial Case 1 when the lone pair is in equatorial plane me ans the Lone Pair bond pair repulsion would be only 2 but in the first case it is total of 4 1 one pair bond pair repulsion then how it co mes out to be the structure of BrF5 used in various places

Which of the following order is correct 1 Cr2 Fet2 Reducing character 2 Mn Crt Oxidising character 3 WO CrO Stability order 4 All of these 87 3 H 4 PR 1 Cr 2 Fe 2 34rch verta 2 Mn 3 Cr 3 31fchten gefa 3 WO CrO Penfura sh 4

The rate constant the activation energy and the Arrhenius parameter of a chemical reaction at 25 C are 3 5 x 10 5s 1 110 5 kJ mol 1 and 6 0 x 10 4 s 1 respectively The value of rate constant at T o is OPTIONS CLEAR SELECTION MARK FOR REVIEW OA 1 5 x 105 s 1 OB 2 0 x 1010 s 1 OC 6 0 x 1014 S 1

The mole fraction of CCl4 g in the vapour in equilibrium with liquid mixture of CCl4 and SiCl4 is 0 3474 The vapour pressure of SiCl4 and CCl4 is 238 3 and 114 9 mm respectively at the same temperature Calculate by weight of CCl4 in liquid mixture a 50 c 30 b 40 d 60

or a particula A B the te constant is 0 693 min 1 If the initial concentration of the reactant A is 1 M then the rate of reaction after 1 minute will be OPTIONS MARK FOR REVIEW CLEAR SELECTION OA 0 35 M min OB 0 14 M min C 0 693 M min

To 5 85gm of NaCl one kg of water is added to prepare of solution What is the strength of NaCl in this solution mol wt of NaCl 58 5 A 0 1 Normal C 0 1 Molar A A B 0 1 Molal D 0 1 Formal

Q 23 The van der Waal s constants a and b for four gases given below Gases ax 103 in atm L mol2 b 102 in L mol Answer A POR 10 S 5 Which gas can be easily liquefied Q P Your Attempt 8 6 Correct answer 4562