Physical Chemistry Questions

35 36 In which of the following transitions will the wavelength be minimum 1 n 6 ton 4 2 n 4 to n 2 3 n 3 to n 1 4 n 2 to n 1 The increasing order of the rate of HCN addition to compound A Dis

Amongst NO ASO CO CIO SO and BO the non planar species are 1 CO SO and BO 2 AsO CIO and SO 3 NO CO and BO 4 SO NO and BO Which of the following is a hypnotic drug 3

36 Total charge required for the oxidation of two moles Mn O into MnO2 in presence of alkaline medium is b 10 F a 5 F d None of these c 20 F 17 If E O 2 x V E Fe 23 Fe2 X V What 45 Ele the

3 Both Tollen s reagent and Fehling solution 4 None of these Given that the equilibrium constant for the reaction 250 g O2 g 250g has a value of 278 at a particular temperature What is the value of the equilibrium constant for the following reaction at the same temperature SO SO g 1 1 8 10 2 8 2 3 6x10 3 6 0x10 4 1 3x10

A solution has a 1 4 mole ratio of pentane to hexane The V Ps of the pure hydrocarbons at 30 C are 440 mm Hg for pentane 120 mm Hg for hexane The mole fraction of pentane in the vapour phase at 16 30 C is 1 0 2 2 0 478 3 0 549 4 0 786

5 The standard reduction potentials for Zn Zn Ni Ni and Fe2 Fe are 0 76 0 23 and 0 44 V respectively The reaction X Y2 Y will be spontaneous when 1 X Ni Y Fe 2 X Ni Y Zn 3 X Fe Y Zn 4 X Zn Y Ni LA FF 3013

The boiling point of an aqueous solution of a non volatile solute is 100 15 C What is the freezing point of an aqueous solution obtained by diluting the above solution with an equal volume of water 11 for water K 0 512 K 1 86 1 0 544 2 0 512 C

is at d aA bB cC dD K K 17 1 mole of NO and 1 mole of O are taken in a 10 L vessel and heated At equilibrium 50 of NO by mass reacts with O according to the equation NO ONO2 O What will be the equilibrium constant for this reaction a 1 b 2 c 3 d 4 25 26 D

5 The molar heat of vaporization of water is 42 kJ mol How much energy is released by the condensation of 3 0 g of water 1 mark a 0 88 kJ b 7 0 kj c 126 kJ d 130 kJ 6 An equilibrium that strongly favors products has 1 mark a a value of Q 1 b a value of K 1 c a value of Q 1 d K Q 7 Consider the reaction CH4 g 202 g CO2 g 2H2O g find the numbers instead of the letters a to g each 1 mark CH 0 5 0 0 5 CO 10 10 H O

in concentration of species X and Y for the reaction X 3Y as a function of time the point of intersection of the two curves represents 1 5 2 2 13 4 3 4 4 Data insufficient to predict 11 14 PM Concentration Y Time

Electrolysis of NaCl solution with inert electrodes for certai period of time gave 600 cm of 1 0 MNaOH in the electrolyt cell During the same period 31 80 g of copper was deposited in a copper voltameter in series with the electrolytic cell The percent current efficiency in the electrolytic cell is 20X Find the value of X At wt of Cu 63 6

chemist reacted 12 762 grams of sodium with water by heating the product until Il the excess water was removed and only the oxide was left The mass of the xide product was 16 991 grams Calculate the moles of sodium

6 The values of A for NH4C1 NaOH and NaCl are respectively 149 74 248 1 and 126 4 ohm cm eq The eq value of A NH OH is 1 371 44 2 271 44 3 71 44 Sim228 21

With respect to hypochlorite chlorate and perchlorate ions choose the correct statement s a The hypochlorite ion is the strongest conjugate base b The molecular shape of only chlorate ion is influenced by the lone pair of electrons of CI c The hypochlorite and chlorate ions disproportionate to give rise to an identical set of ions d The hypochlorite ion oxidizes the sulfite

1 Following limiting molar conductivities are given as Am H SO4 x S cm mol 1 Am K SO4 y S cm mol 1 zS cm mol 1 NEET Odisha Am CH COOK A m in S cm mol 1 for CH3COOH will be a x y 2z b x y z c x y z x y

12 A compound is made by mixing cobalt III nitrite and potassium nitrite solutions in the ratio of 1 3 The aqueous solution of the compound showed 4 particles per molecule whereas molar conductivity reveals the presence of six electrical charges The formula of the compound is a Co NO 2KNO c K Co NO b Co NO 3KNO d K Co NO 4

Match the geometry given in column A with the complexes given in column B in Geometry A Complex B 1 Octahedral II Square planar III Tetrahedral 1 I P II Q III R 3 1 R II Q III P P Ni CN Q Ni CO R Fe CN 2 I R II P III Q 4 I Q II P III R IDE

2 When 17 4 g of a solid is dissolved into 25 0 mL of water the volume of the solution becomes 28 2 mL What is the percent W V concentration of the solutio a 88 7 c 69 6 d 38 3 e 61 7 b 30 4

The solubility of Cul2 s Ksp 1 1 x 10 12 in 0 15 M Nal aq solution is S 7 33 x 10 12 M S 1 35 x 10 6 M S 4 89 x 10 11 M 1 Ksp S S 0 15 2 Ksp S 0 15 25 2 3 Ksp S 25 0 15 S Ksp 0 15 S Ksp 0 6 1 2 S Ksp 0 15 2

4 AIEEE 2009 2 The Gibbs energy for the decomposition of Al2O3 at 500 C is as follows 7 3 Al O3 4 3 Al 0 AG 966 kJ mol The potential difference needed for electrolytic reduction of Al O3 at 500 C is at least 1 4 5 V 3 2 5 V The reduction potenti 2 3 0 V 4 5 0 V AIEEE 2010

125 The potential of the cell at 25 C is Pt H CH3COONa 0 1 M 1 atm CH COOH 0 01 M NH4C1 H Pt 0 2 M 1 atm NH OH 0 1 M Given pk of CH3COOH and pK of NH OH 4 74 1 0 04 V 2 0 04 V 3 0 189 V 4 0 189 V

b Calculate the volume of water which could be added to 20 ml of 0 65 m HCl to dilute the solution to 0 2 m 1 a What happens when red blood cells are placed in 0 1 NaCl solution b Calculate the osmotic pressure of 0 25 M solution of urea at 370C R 0 083 L bar mol k

41 43 44 A Inorganic salt 42 Reddish brown fumes 45 In redox reaction H O2 oxidises K Fe CN 6 into K Fe CO and NO3 ions in acidic medium than how many moles of H2O2 will react with Imole of K Fe CN 1 5 moles 2 9moles 3 8moles 4 30 5moles K Cr O7 conc H SO4 AAJ KA TOPPER Which is correct statement regarding above observation 1 It confirms the presence of Cl ions 2 It confirms the presence of Br ions 3 It confirms the presence of both ions 4 It neither confirms the presence of CT nor Br ions unless it is passed through NaOH solution A buffer solution contains equal concentration of X and HX The k for X is 10 10 The pH of the buffer solution is 1 4 2 7 3 10 4 14 Which of the following drugs is a tranquilizer and sedative 1 Sulphadiazine 2 Papaverine 3 Equanil 4 Mescaline Which one of the following reacts with HBr 1 2 3 H C OH OH CH CH OH OH

10 In passing 3 F of electricity through three electrolytic cells connected in series containing Ag Ca and Al ions respectively The molar ratio in which the three metal ions are liberated at the electrodes is 1 1 2 3 2 2 3 1 3 6 3 2 4 3 4 2 Given that 219 1 2e F 0 54 V

1 1 8 10 2 3 6x10 Which is a pair of geometrical isomers CI Br Cl Br H Br H Cl CH Br 3 6 0x10 Br H H CI 4 1 3x10 III 3 II and IV Br 1 II 1 I and II 2 I and III 4 III and IV The temperature of a sample of gas is raised from 127 Cto 527 C The averago kinetic anorm IV CH

29 Find out value of expression x y for complex compound Zn bcac x Total number of O Zn O bond angle s in the compound where 3 y Total number of sp Hybridized atom s in the compound

117 The variation of equivalent conductance of strong electrolyte with concentration is correctly shown in the figure 1 Acq 3 Aeg C 2 Aeq 4 Aeq C

134 The electrical conductivity of a solution serves as a means of determining the end point in a chemical reaction involved in the titration of acids bases or precipitation Which of the following conductometric titrations represent the curve of HCI vs NH4OH x axis Volume of alkali added y axis Conductivity 1 3 End point ED End point 2 4 Too End point End point 001 831

Boyle s temperature of a vander Waal s gas is 350 K Which of the following statement s is are correct for the gas A The gas can t be liquefied at 300 K B The gas can be liquefied at 150 K C The gas shows negative deviation at low pressure and 275 K D The gas shows positive deviation at any pressure at 400 K

A mixture of 4 76e 02 mol of C2H6 1 41e 02 mol of N2 1 14e 02 mol of NH3 and 2 46e 02 mol of C2H4 is placed in a 1 0 L steel pressure vessel at 1624 K The following equilibrium is established 3 C2H6 g N2 g 2 NH3 g 3 C2H4 g At equilibrium 7 41e 03 mol of NH3 is found in the reaction mixture Calculate the equilibrium pressures of all gases in the reaction vessel and the value of KP for the

4 Resistance of 0 2 M solution of an electrolyte is 50 22 The specific conductance of the solution is 1 3 S m If resistance of the 0 4M solution of the same electrolyte is 260 2 its molar conductivity is 1 6250 S m mol 2 6 25 x 10 4 S m mol 3 625 x 10 4 S m mol 4 62 5 S m mol AIEEE 2011

Which is incorrect regarding plasma level curve Select one a Therapeutic range should be lower than MEC O b Absorption phase comes first then Elimination phase Oc Plot of plasma concentration with time d Absorption phase end at maximal drug level obtained with de

c 1 cm d 1 cm 7 The resistance of a decinormal solution of a salt occupying a volume between two platinum electrodes 1 80 cm apart and 5 4 cm in area was formed to be 32 The specific and equivalent conductivity 2 ohm respectively in their proper units are a 104 1 and 0 0104 0 0104 and 104 0 b 208 2 and 0 0208 d none of these

hydrated 7 Which one of the following statements is not correct in respect of lyophilic sols a There is a considerable interaction between the dispersed phase and dispersion mediu b These are quite stable and are not easily coagulated c They carry charge d The particles are hydrated

Specific conductance of 0 01 M KCl solution is x ohm cm When conductivity cell is filled with 0 01 M KCl the conductance observed is y ohm 1 When the same cell is filled with 0 01 M H SO4 the observed conductance was z ohm cm The specific conductance of 0 01 M H SO4 is a xz c xz y b z xy d xy z rod for the complete decomposition

0 N and O are converted to monocations N and O respectively which is wrong stateme 1 In N the N N bond weakens 2 In O the 0 0 bond order increases 3 In O the paramagnetism decreases 4 N becomes diamagnetic

34 Ethane gas is obtained in Kolbe s electrolysis of CH COONa according to the following reaction CH 2CH 000 I 200 2e CH What volume of gas ethane gas at S TP would be obtained by a current of 0 5 amp 80 efficient if the current is passed for 965 min a 1 8 L b 2 688 L c 3 45 L d 11 2 L

Study the data you collected for Trials 3 and 4 When the amplitude decreases what happens to the frequency The frequency stays the same O The frequency increases The frequency decreases

13 Match the geometry given in column A with the complex given in column B using the codes given below Column B Column A a Cu NH 2 b Ag NH i Tetrahedral ii Octahedral iii Square planar iv Trigonal bipyramidal Linear c Fe CO d Cr H O e NiC12 V a i e ii d iii a iv c v b b i d ii e iii a iv c v b c i d ii e iii b iv a v c d i c ii e iii h iv a x d

Negative Marks In all other cases An ideal gaseous mixture of ethane C H and ethene C H occupies 28 litre at 300K 1atm The mixture reacts completely with 128 gm O to produce CO and H O Mole fraction at C H in the mixture is Report answer after multiplying with 10 Nearest integer R 0 08 litre atm K mole V Litre of solution A Resistance 50 ohm is mixed with V Litre of solution B

CHEMISTRY Consider the following E values E LLi 3 05 V E Cu2 Cu 0 34 V Under similar conditions the potential for the reaction Cu 2Lit Cu 2Li is 1 3 39 V 2 3 39 V 3 2 69 V 4 2 69 V

5 Total vapour pressure of mixture of 1 mol volatile component B PA 100 mmHg and 3 mol of volatile component B PB 60 mmHg is 75 mm For such case H H le CH H H 1 There is positive deviation from Raoult s law 2 Boiling point has been lowered 3 Force of attraction between A and B is smaller than that between A and A or between B and

26 In a first order reaction the concentration of reactants decreases from 400mol L to 25 mol L in 200 seconds The rate constant for the reaction is a 1 01386 S 1 b 2 10 S 1 d 3 4 x 10 S c 1 386 x 10 2S 1 reactio C for a first order

1 Given Efe Fe 0 036 V EFe Fe 0 439 V The value of standard electrode potential for the charge Fe aq e Fe aq will be 2 0 385 V 4 0 270 V AIEEE 2009 1 0 072 V 3 0 770 V 271

2 A compound contains C H N only 3 1 gm of this compound gives 4 4 gm of CO on combustion and in ano experiment during estimation of nitrogen 6 2 gm of this compound gives 3 4 gm of NH Find percent composition of compound

11 2 If is 8 The equivalent conductance of NaCl at concentration C and at infinite dilution are and is given as 1 B C 3 B C 2 B C 0 4 B C JEE Main 2014 Single 1

2 Xenon trioxide XeO3 forms xenate ion in alkaline medium XeO NaOH Na HXCO But the xenate ions slowly disproportionate in alkaline solution as Na HXeO NaOH Z Xe O H O The compound Z is expected to be 1 Na XeO 2 Naz XeO4 3 Na4 XeO6 4 Na4 XeO

Base catalysed condensation between the following compounds followed by dehydration gives methyl vinyl ketone 1 HCHO and CH COCH3 2 HCHO and CH CHO 3 Two molecules of CH3CHO 4 Two molecules of CH COCH

CH NH 0 12 mole pK 3 3 is added to 0 08 moles of HCl and the solution is diluted to one litre resulting pH of solution is 1 10 7 2 3 6 3 10 4 4 11 3 64 g non volatile solute is added to 702 g benzene The vapour pressure of benzene has decreased from 200 mm of Hg to 180 mm of Hg Molecular weight of the solute is 1128 2161 3196 41256

The hydrolysis of methyl acetate in alkaline medium follows 2nd order rate law CH3COOC H5 OH CH3COO C H5OH ate k CH COOC H5 OH The value of k at 298 K is found to be 0 137 Lmol s If initial conc of each reactant is 0 05 M The time ta 5 ethyl acetate to be hydrolysed will be a 7 35 s b 74 s c 740 s d 7 4 min