Physical Chemistry Questions

2 2 3 3 4 1 5 54 If the specific conductance of 1 M H SO4 solution is 26 102 S cm mol then the equivalent conductivity would be 1 1 3 102 S cm 1 3 13 S cm mol 2 1 6 102 S cm 4 1 3 x 103 S cm mol

The conversion of ozone into oxygen is exothermic Under what conditions is ozone the most stable 203 g 30 g Question Type Single Correct Type 1 2 At high pressure and high temperature 3 At low pressure and low temperature 4 At high pressure and low temperature At low pressure and high temperature

a Give reasons for the following 3 i Mn is a good oxidising agent ii EM M values are not regular for first row transition metals 3d serie iii Although F is more electronegative than O the highest Mn fluori is MnF4 whereas the highest oxide is Mn O b Complete the following equations i 2CrO2 2H ii KMnO heat

Incorrect statement among the following is O In SO3 all the atoms lie in one plane O Triple bond between two carbon atoms is made up of one sigma and two pi bonds O O SF6 molecule has a regular octahedral geometry Percentage s character in sp d hybridization is 16 67

120 Given the following cell at 25 C H CH COOH NaOH H Pt 1 atm 10 M 10 3M 1 atm What will be the potential of the cell Given pk of CH3COOH 4 74 a 1 0 42 V 2 0 42 V Pt 3 0 19 V 4 0 19 V

Ferric chloride FeC13 reacts with silver nitrate AgNO3 to form ferric nitrate Fe NO3 3 and silver chloride AgC1 a Write the balanced chemical equation of the reaction b If 108 5 moles of FeC13 is combined with 76 8 moles of AgNO3 how many moles of AgCl is produced c How many grams of AgC1 is produced d Which reactant is the limiting reagent e Which reactant is the excess reagent

Q 10 Water at the rate of 3 8 kg s is heated from 38 to 55 C in a shell and tube heat exchanger On the shell side one pass is used with water as the heating fluid 1 9 kg s entering the exchanger at 93 C The overall heat transfer coefficient is 1419 W m C and the average water velocity in the 1 9 cm diameter tubes is 0 366 m s Because of space limitations the tube length must not be longer than 2 5 m Calculate the number of tube passes the number of tubes per pass and the length of the tubes consistent with this restriction Assume LMTD correction factor F 0 9 for two passes

Consider the following graph for a fixed mass of gas T2 V The correct relation between T T2 and T3 is O T T T3 O T3 T T T3 O T T3 T1 O T T T3

39 10800 C of electricity passed through the electrolyte deposited 2 977 g of metal with atomic mass 106 4 g mol The charge on the metal cation is 1 4 2 3 Gal 11 3 2 ll the go 4 1 rion of iron be most

An excess of AgNO3 is added to 100 mL of a 0 01 M solution of dichlorotetraaquachromium III chloride The number of moles of AgCl precipitated would be 1 0 01 2 0 001 3 0 002 4 0 003

10 3 The boiling point of a solution containing 3 x kg non volatile substance present in 50 10 3 kg water is 373 5 K the molar mass of the substance Kb 0 52 K kg mol a 36 2 g mol c 60 6 g mol b 58 49 g mol 1 d 52 4 g mol

arboxylic acids are weak acids and dissociate in water What species is formed by the dissociation of benzoic acid in aqueous solution A benzene B benzoate ion C benzaldehyde D phenol E toluene

Consider the following statements a Bond angle of ammonia is greater than bond angle of H O b In BeCl central atom is sp hybridised c In CCl4 maximum four atoms are present in a plane The correct statement s is are Oa and c only O conly O a and b only O a b and c

Which one of the following is NOT an expression for Raoult s law for a binary solution containing two components A and B a PA PA XA b PTotal PA XA PB XB c AP PB XB d AP PA XA

64 mL of an unknown gas diffuses in same time as 128 mL of methane gas under identical conditions molar mass of unknown gas is 32 g mol 1 O 48 g mol O 96 g mol hr m O 64 g mol

Consider the following statements a At very low temperature intermolecular forces between gaseous molecules become significant b For ideal gas Z 1 at all temperature c At high pressure all gases have Z 1 The correct statements are O a and b only Ob and c only Oa and c only O a b and c

Which of the following species can function both as oxidizing as well as reducing agent 1 Mn 2 NO 3 CIO 4 CIO One Faraday of electricity is passed through molten Al2O3 aqueous solution of CuSO and molten NaCl taken in three different electrolytic cells connected in series The mole ratio of Al Cu and Na

The H O fuel cell have cell reaction 2H2 g O2 g 2H O and cell potential 1 23 V The half cell O2 g 2H O 4e 40H aq has E 0 4 V then find E for 2H O 2e H g 2 H 1 0 41 V 2 0 83 V 3 0 41 V 4 0 83 V R PT X 742 78 X AG A

Consider the following statements for kinetic molecular theory of gases a Particles of a gas move in all possible directions in straight lines b At any particular time different particles in the gas have different kinetic energies c Collisions of gas molecules are perfectly inelastic in nature The correct statement s is are O a only Ob only a and b only a b and c

i 500 Mg mass of juml ii 3 34 x 10 24 g mass of hydrogen molecule 7 Express the following in the designated units i 1 54 mm s to pm s ii 25 gL to mg dL iii 25 L to m 3 iv 2 66 g cm 3 to g m v 4 2 Lh 2 to mL s 2

Consider the following graph for a fixed mass of gas P E V The correct relation between T T2 and T3 is T2 T O T T T3 O T3 T T O O T T3 T T T T3

The rate constant for the first order reaction below is 0 0617 s A B 1st attempt l S

118 Given the standard potential of the following at 25 C E 0 95 V MnO Mn Mn3 Mn 1 51 V E The standard potential of MnO Mn is 2 obot t 1 0 56 V 2 2 46 V 3 1 23 V 4 1 23 V

N and O are converted to mono positive cations N and O respectively Which is incorrect According to Molecular orbital theory 1 N becomes diamagnetic 3 In O the bond order increases 2 In O paramagnetism decreases 4 In N the N N bond is weakened

The decomposition of phosphine PH3 on tungsten at low pressure is a first order reaction It is because the 1 rate is independent of the surface coverage 2 rate of decomposition is very slow 3 rate is proportional to the surface coverage 4 rate is inversely proportional to the surface

COH COH COCH 1 2 4 75 of the first order reaction completed in 32 min 50 of the reaction was completed in 1 24 min 2 8 min 3 16 min 4 4 min A diatomic gas belonging to group 15 combines with a halogen to form a trihalide which is fairly stabl

that of potential energy Assertion Angle and angular displacement are dimensionless quantities Reason Angle is equal to arc length divided by radius

28 8 why Is Which of the following statement CORRECT incorrect A Orbital means electron density same B For orbitals with the same quantum number same shape the larger the orbital the higher the energy Experimentally we can measure the shape of an orbital 10 doidW C TRUE aceaeplo lo aaayt adtwollo D The 2s and 2p orbitals are degenerate for a carbon Atom xatons laswol WIJ 6

The compound of the highest acidity is OH b c 2 2 Dimethylbutane OH HO 2 3 Dimethyl 2 butene undergoes catalytic hydrogenation to give a 2 3 Dimethylbutane b 2 Methylpentane OH d 3 Methylpentane OCH3 d 11 OH 12

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 ration of the concentrations of the conjugate acid HIn and base In forms of the indicator by the expression Hin In Hin pH PK In O log O jog pkin pH log pH pKin In Hin log In THinl pk In pH

65 A diatomic gas belonging to group 15 combines with a halogen to form a trihalide which is fairly stab and inert The trihalide is 1 NCL 2 PCL 66 Which of the following statement incorrect 3 BiF 4 NF

K Cr O7 is the powerful oxidising agent in acidic medium In the same medium if oxidising powe of Cr O7 decreases by x volts when pH of the solution increases from 0 to 5 at 298 K then the value of 10x will be Take 2 303RT F 0 06

Mechanism X2 Y2 2XY is given below i X X X fast ii X Y XY Y slow iii X Y XY fast The overall order of the reaction will be of a hypothetical reaction 1 2 3 1 5 2 O 4 1

5 mL acetone is mixed with 100 mL of water The vapour pressure of water above the solution will be a Equal to the vapour pressure of pure water b Equal to the vapour pressure of the solution c less than the vapour pressure of the pure water d more than the vapour pressure of

A liquid has vapour pressure 15 x 10 Nm 2 at 298 K If the solution contains 0 2 mole fraction of a solute the vapour pressure of the solution will be a 2 8 x 10 Nm c 7 0 x 10 Nm b 7 x 10 Nm 2 d 17 5 x 10 Nm

Number of gold atoms in 300 mg of a gold ring of 20 carat gold pure gold is 24 carat ar A 4 5 100 B 6 8 x 1015 C 7 6 x 1020 D 9 5 100 From a container having AA Dvinn MON 1023

of iron are removed then the iron left If a sample of Ferric sulphate Fe SO contains 7 2 moles of O atoms then the number of S atoms in given sample are A 1 8 N B 1 2 N C 1 6 N D 1 4 N

In which of the following are the crystal field cleavage and crystal field stability energies in Dq for Ni H2O 6 Cl2 are respectively given correctly A 10 Dq 12 Dq 3 10 Dq 8 Dq C Dq 10 Dq D 12 Dq Dq E 8 Dq 10 Dq

select the correct statement A Animal hides are colloidal in nature Emulsions can be diluted with any amount of the dispersion medium on the other hand disperse liquid when mixed forms a separate layer Emulsions do not show brownian motion and Tyndall effect For a colloid solution the values of colligative properties are of small order as compared to values shown by true solutions at same concentrations B C D

The rate of the reaction 2NO Cl 2NOCI is given by the rate equation rate k NO C1 the value of rate constant can be increased by 1 Increasing the concentration of NO 2 Increasing the concentration of the Cl 3 Increasing the temperature 4 all of these

A solution is a mixture of 0 05 M NaCl and 0 05 M Nal The concentration of iodide ion in the solution when AgCl just starts precipitating is equal to Ksp AgCl 1 x 10 10 M K AgI 4 x 10 6 M A 2 10 7 M B 2 x 10 M C 4 x 10 6 M D 8 x 10 15 M

Consider the following electrochemical cell Cu2 Cul H H Pt to calculate the maximum activity of copper ions Cu2 in solution due to oxidation of a copper strip immersed in sulfuric acid H SO4 at 25 C 101 kPa and PH 2

For the reaction 3BrO BrO 2Br in alkaline aqueous solution the value of the d BrO dt second order rate constant in BrO in rate law for and as 10 M s The rate constant in M s when the rate law is written as d Br dt was found to be 0 06 is b then the value of a b 100 is d BrO dt is a

2 moles of octane in beaker 1 and 3 moles of nonane in beaker 2 are enclosed in a chamber A in beaker 3 2 moles of octane and 3 moles of nonane are mixed and this beaker is placed in chamber B At equilibrium at the same temperature vapour pressure in chamber A will be a greater than that in chamber B b less than that in chamber B c Same as that in chamber B d Greater or less than in chamber B depending upon temperature

What is the activation energy of a reaction if its rate doubles when the temperature is raised from 20 C to 35 C R 8 314 J mol K 1 15 1 kJ mol 3 269 kJ mol O por 262 2 342 kJ mol 1 4 34 7 kJ mol

A room 4 x 4 m square by 3 m high has one side wall maintained at 260 C the floor is maintained at 90 C The other four surfaces are perfectly insulated Assume that all surfaces are black Calculate the net heat transfer between the hot wall and the cool floor

1 2 4 4 h 3 4 4 Solubility product K of saturated PbCl in water is 1 8 10 mol dm What is the concentratio of Pb in the solution 1 0 45 10 mol dm 3 0 9 10 mol dm 2 1 8 10 mol dm 4 2 0 10 mol dm

7 0 635 x 10 kg of a substance of molar mass 190 10 kg mol was dissolved in 30 5 x 10 kg of a solvent If the depression in the freezing point is 0 62 C find the molal depression constant of the solvent 2 marks

122 Given electrode potentials are Fe e Fe 1 2e210 E for the cell reaction cell 2Fe 21 Fe 1 is 1 2 x 0 771 0 536 1 006 V 2 0 771 0 5 x 0 536 0 503 V 3 0 771 0 536 0 235 V mazum 4 0 536 0 771 0 236 V E 0 771 V E 0 536 V

C mixed proportions D none of these The respective ratio of weight of oxygen in samples of pure CuO and Cu O if both samples contain same mass of copper is A 1 2 B 1 1 C 2 1 D none of these