Physical Chemistry Questions

aq NaCl d aq CuCl 21 When an aqueous solution of H SO4 is electrolysed the product at anode is lag a H d 0 b OH gian oo c So 2 An 201 eous soluti

A mixture contains 1 mole of volatile liquid A P 100 mm Hg and 3 moles of volatile liquid B P 80 mm Hg If solution behaves ideally the total vapour pressure of the distillate is a 85 mm Hg c 90 mm Hg b b 85 88 mm Hg d 92 mm Hg

If a is the fraction of ammonia present by volume in an equilibrium mixture made from one volume of N and three volumes of H and P is the tota pressure then a c a 1 a a P a 1 a a P b d a 1 a a P a ap 1 a A

3 a chloroacetaldehyde is more reactive than acetaldehyde because a chlorine atom has I effect and decreases ve character of carbony carbon b chirioncatom has I effect and decreases ve charactor of carbony carbon c Methyl group has 1 effect and increases ve charactor of carbony carbon d chiorine atom has I effect and increses ve character of crbonyl carbon

14 A giant molecule contains 0 25 of a metal whose atomic weight is 59 Its molecule contains one atom of that metal Its minimum molecular weight is 1 5900 2 23600 3 11800 4 100 59 0 4

a H b Na 25 A dilute aqueous solution of CuSO4 is electrolyzed using platinum electrodes The products at the anode and cathode are a O2 H2 c O 2 Cu d S 0 H b H 2 02

Hydrochloric acid HCI reacts with sodium hydroxide NaOH to form sodium chloride NaCl and water If AH 56 13 kJ mol and AS 79 11 J mol K wh the entropy change of the universe for this reaction at 20 C 3966 J K 271 J K 188 J K 2807 J K ctem is at equilibrium

The surface tension of which of the following liquid is maximum AIPMT Prelims 2005 1 H O 3 CH OH 2 CH 4 C H OH

mportance of the concept of enthalpy According to the first law of thermodynamics AU q w q PAV considering only P V work At constant volume AV 0 AU 9v Thus at constant volume heat absorbed or released qv by the system is equal to the change in internal energy of the system So we can determine the change in internal energy in a chemical reaction at constant volume by determining the amount of heat that is exchanged in the reaction However reactions are seldom carried out at constant volume as it is difficult to maintain constant volume during most reactions

The ground state energy in J of hydrogen atom is X The minimum energy in J required to promote an electron from n 1 to n 2 in Het is 4X 1 3X 2 3 3 3X 4 3

A 2B 2C Initially 2 mole of A and B are taken in 10 lit flas at equilibrium 1 mole of C is formed then calculat K for given reaction 1 6 66 2 3 33 3 2 22 4 1 11

Determine the percentage composition by mass of a mixture of anhydrous sodium carbonate and sodium bicarbonate from the following data wt of the mixture taken 2g Loss in weight on heating 0 11 gm

8 The amount of energy released when 10 2 atoms of Cl vapours are converted to CI ions according to the equation Cl g e Cl g is 58 10 10 J Calculate the AH of Cl atom in kJ mol and eV atom a 0 036 eV atom b 3 48 eV atom e 0 038 eV atom d 0 361 eV atom

24 If Pt is used as cathode in the electrolysis of aqueous NaCl solution the ion reduced at cathode is a H b Na c OH d Cl luged using platinum electrodes The products a

6 5 g of C H O is dissolved in 450 g of CH CN Nalorphene C H NO3 similar to morphine is used to combat withdrawal symptoms in narcotic users Dose of nalorphene generally given is 1 5 mg Calculate the mass of 1 5 10 m aqueous solution required for the above dose ring 350

Resistance of a conductivity cell filled with a solution of an electrolyte of concentration 0 1 M is 100 The conductivity of this solution is 1 29 S m Resistance of the same cell when filled with 0 02 M of the same solution is 520 2 The molar conductivity of 0 02 M solution of the electrolyte will be 1 124 x 10 4 S m mol 1 2 1240 x 10 4 S m mol 1 3 1 24 x 10 4 S m mol 1 4 12 4 x 10 4 S m mol

49 For the synthesis of ammonia from its elements 3H g N g 2NH g the equilibrium constant K 6x 10 at 300 K and AH 24 kCal mol Calculate equilibrium constant at 600K assuming no change in AH between 300 K and 600K Given e 20 2 10 isted in the table are forward and reverse rate constants for the reaction 2NO g N g 0 g k M s k M s 1 1 x 10 6

A compound of X and Y has equal mass of them If their atomic weights are 30 and 20 respectively Molecular formula of that compound 1 X Y 3 X Y 3 2 X Y3 4 X Y 3

2 O2 Na d H S 0 20 The passage of current through a solution of certain electrolyte results in the evolution of H g at cathode and Cl g at anode The electrolytic solution is 101000103 a Water b aq H SO4 aq NaClimut d aq CuCl2 When an 8

The solubility of BaSO4 in water 2 42 x 10 gl 1 at 298 K The value of solubility product Ksp will be Given molar mass of BaSO4 233 g mol 1 1 08 x 10 10 mol L 2 2 1 08 x 10 12 mol L 2 3 1 08 x 10 14 mol L 2 4 1 08 x 10 8 mol L 2

An aqueous solution of KIO3 was treated with excess of KI solution The solution is acidified with HCl The liberated 12 consumed 10ml of 1 0M thiosulphate solution to decolourise starch iodine complex Then millimoles of KIO3 consumed are

Calculate the surface area per gm of a catalyst that adsorb 1000 ml of N gas at STP to form a monolayer at their surface Surface area of a N molecule is 1 62 10 5 cm 2200ML 1000 L 1 4 35 cm 2 4 35 x 107 m 3 4 35 x 107 cm 2 2 4 435 cm foluemulsion

9 One of the lines in the spectrum of atomic hydrogen has wave number 533 16 cm What is the frequency of this line a 5 623 x 106 s 1 c 1 598x 10 3 S 1 b 1 876x 10 S 1 d 1 598x 10 4 S 1

Comment on the reactions of dihydrogen with i chlorine ii sodium and iii copper II oxide

40 of a mixture of 0 2 mole of N and 0 6 mole of H react to give NH3 according to the equation N g 3H g 2NH3 g at given temperature and pressure Then the ratio of the final volume to the initial volumes of gases are as a 4 5 c 7 10 b 5 4 d 8 5

If the boiling point of ethanol molecular weight 46 is 78 C the boiling point of diethyl ether molecular weight 74 is 1 100 C 2 78 C 3 86 C 4 34 C 13

53 When a electron in H atom jumps from n 4 to n 1 ultra violet light is emitted if the transition corresponds to n 4 to n 2 which of the following light will be emitted a ultraviolet c infrared b visible d None of these

The ratio of number of moles of AgNO3 Pb NO and Fe NO required for coagulation of a defini amount of colloidal sol of silver iodide prepared by mixing AgNO with excess KI will be A 1 2 3 B 3 2 1 D 2 3 6 ired to protect 100 ml of gold sol f C 6 3 2 Joabe or

probability density plots of ls and 2s orbitals are given in figure O 1s O 2s The density of dots in a region represents the probability density of finding electrons in the region On the basis of above diagram which of the following statements is incorrect a 1s and 2s orbitals are spherical in shape b The probability of finding the electron is maximum near the nucleus c The probability of finding the electron at a given distance is equal in all directions d The probability density of electrons for 2s orbital decreases uniformly as distance from the nucleus increases

Among following standard enthalpy of format non zero for 1 C graphite 3 H g 2 Br 1 4 12 g

A solution of NaOH is 4 g L 1 What volume of HCI gas at STP will neutralize 50 ml of the alkali solution 1 224 ml 3 11200 ml 2 112 ml 4 22 4 ml

238 A closed vessel with rigid walls contains 1 mol of 22U and 1 mol of air at 298 K Considering 92 92 82 complete decay of 232 Uto 20 Pb the ratio of the final pressure to the initial pressure of the system at 298 K is 2015

d bcc and hcp 3 The number of octahedral void in bcc structure is a 0 b 1 c 2

KO H O KOH H O O 28 4 g KO when treated with excess H O gives only 0 34 g H O according to the above reaction Determine the yield of H O KO H O KOH H O O 28 4 g KO at 46 curica 3 0 34 g H O fa si 2

5 When there can be more deviation in the behaviou of a gas from the ideal gas equation PV nRT 1 At high temperature and low pressure 2 At low temperature and high pressure 3 At high temperature and high pressure 4 At low temperature and low pressure 0

Calculate the volume of O2 at 1 atm and 273 K required for the complete combustion of 2 64 L of acetylene C H at 1 atm and 273 K 2C H g 50 g 4CO2 g 2H 0 1 a 3 6 L b 1 056 L c 6 6 L d 10 L

C Change of medium from acidic to D Change in medium from acidic to basic will change the nature of product A sample of steel weighing 0 30 g was subjected to a chemical reaction to convert its sulphur impurity to H S g The evolved gas required 2 40 mL 0 02 N iodine solution Which of the following statement s is are true A B C A lodine is reduced to iodide B H S is oxidized to S C Steel contain 0 256 of S by weight D The reaction of H S with I is a precipitation reaction rather than a redox reaction TCH THE COLUMN

PROBLEM 48 A given sample of Na SO4 contains 6 02 1022 SO2 ions Calculate i number of Nations ii number of formula units and iii weight of the sample C00 1022 fomulo unite

2 In ion dipole interaction potential energy depends on the distance between interacting particles which of the following relation is correct a U x 2 2 c U x 6 r b Uc d Uc 4 Y r

20 The following graph represents the total energy of homonuclear diatomic systems AA BB CC and DD as a function of their internuclear distance E O FB Based on the above graph select the correct statement A The molecule A is stable B The correct order of bond length is B D C C has a greater bond dissociation energy than D D A has a greater bond dissociation energy than B Page 7

Match the List I Phenomenon associated with electromagnetic radiation with List II Part of electromagnetic spectrum and select the correct code from the choices given below the lists List Il Visible radiation Microwave 1 II III IV List I Doublet of sodium A Wavelength corresponding to temperature associated with B the isotropic radiation filling all space Wavelength emitted by atomic hydrogen in interstellar C space Wavelength of radiation arising from two close energy D levels in hydrogen 1 1 A II B III C IV C 2 1 A II B III B IV C 3 1 B II A III D IV A 4 1 D 11 C III A IV B Short radiowave X rays 2014

2 Classification of Ele a Be and Mg are alkaline earth metal b K have larger radii than Ca c All d block elements are transition elements d He ion have larger size than F Incorrect statements is are 1 a c d 2 b c 3 a d

Which one of the following metals can not be obtained on electrolysis of aqueous solution of its salts a Mg d c Cu d Cr b Ag

The enthalpies of combustion of carbon and carbon monoxide are 390 kJ mol and 278 mol respectively The enthalpy of formation of carbon monoxide is a 668 kJ mol c 112 kJ mol 1 b 112 kJ mol d 668 kJ mol 1

12 The pressure of H required to make the potential of H electrode zero in pure water at 298 K is NEET 2016 1 104 atm 3 10 12 atm 2 10 14 atm 4 10 10 atm

A zero order reaction is one whose rate independent of 1 Temperature of the reaction 2 The concentration of the reactants The concentration of the products Activation energy

One gm metal M weight of metal a 33 35 T was discharged by the passage of 1 81 x 1023 electrons What is the atomic b 133 4 c 66 7 d None of these MnO in presence of

37 The lowering of vapour pressure of a solvent by addition of a non volatile solute to it is directly proportional to 1 The strength of the solution 2 The nature of the solute in the solution 3 The atmospheric pressure 4 All

Four moles of electrons were transferred from anode to cathode in an experiment on electrolysis of water The total volume of the two gases dry and at STP produced will be approximately in litres a 22 4 c 67 2 b 44 8 d 89 4

If 224 mL of a triatomic gas has a mass of 1g at 273 K and 1 atm pressure then the mass of one atom is 1 8 30 10 23 g 35 53 x 10 230 g 2 2 08 x 10 23 4 6 24 x 10 23 g