Physical Chemistry Questions

In the following gaseous reaction 2A 4B C The concentration of B was found to increase by 5 x 10 mol L in 10 seconds The rate of reaction is mol L s 1 5 x 10 2 4 x 10 mol L 3 1 25 x 10 mol L 4 20 10 mol L s 82 4 10 000 ohm cm eq 2A4B CB 105 10 mol Larat t aff 1 5 x 10 2 4 10 3 1 25 10 4 20 x 10 mol L mol LS mol Ls mol L s

The degree of dissociation of Ca NO3 2 in a dilute aqueous solution containing 14g of the salt per 200g of water 100 C is 70 percent If the vapour pressure of water at 100 C is 760 cm Calculate th vapour pressure of the solution A 746 3 mm of Hg C 740 9 mm of Hg B 757 5 mm of Hg D 750 mm of Hg

MnO 5e 8H Mn 4H O then Nernst equation for ERP is A EMnO Mn2 E C 0 059 D B EMno Mn E log MnO4 H 8 Mn 5 log EMPO M2 E EMnO Mn E 0 059 x 5log 0 059 Mn MnO 5 0 059 Mn MnO4 H 8 MnO4 H 8 log

If you need to make 200 0 mL of an aqueous solution of 0 010 M H O from a 9 8 M stock solution of H O this is the actual concentration it is sold at what volume of H O stock would you need to do the dilution directly If you were to do a series of 10x dilutions instead how many would you need to do 2 pts

10 grams of a solution contains mixture of NaOH and Na CO when titrated in presence of phenolphthalein indicator 17 5 ml 1M HCI was required In separate titration 10 gm of same stock solution when titrated using methyl orange indicator 22 5 ml of the same acid was required Mass percentage of NaOH in the mixture is

d III IV II I li pH of a saturated solution of Ba OH is 12 the value of its K is I III IV I 13 4 00 x 10 6 M c 5 00 10 6 M b 4 00 x 10 7 M d 5 00 x 10 7 M

The cell consists of three compartments separated by porous barriers The first contains a cobalt electrode in 5 00 L of 0 100 M cobalt II nitrate the second contains 5 00 L of 0 100 M KNO3 and third contains 0 1 M AgNO3 Assuming that the current within the cell is carried equally by the positive and negative ions tabulate the concentrations of ions of each type in each compartment of the cell after the passage of 0 100 mole electrons Given Co2 2e Co Age Ag E 28 V E 0 80 V Co 0 20 M NO 0 10 M Co 5 0 L 1 10 10 M NO 1 10 10 M K 1 1 5 0 L 1 0 10 M NO 0 10 M Ag 1 1 5 0 L Ag

38 At STP a container has 1 mole of He 2 mole Ne 3 2 2 mole O and 4 mole N Without changing total pressure if 2 mole of O is removed The partial of O will be decreased by 2 pressure 1 26 2 40 3 58 33

Which one is correct among the following 1 A H CH g AH comb C grap AH AHO comb H g AH CH g comb 2 AH comb CH g A H CO g A H H O C AH CH g 3 A H CH g AH ublimation C graphite 2BE H 4BEC H 4 AH com CH g 4BEc x 4BEC BEO o 2BEC o AH H O 4BE o

2 27 An element X has its electronic configuration of 87 K shell is n 5 s and it has total no of electrons in its outermost penultimate and antipenultimate shell are 2 8 and 25 respectively than find out no of unpaired e in element X in their ground state 1 5 2 7 3 4 4 3 3 Fe Z 26 ca arft 1 5 4 Co Z 27 2 7 4 344 334344 2 8325 TEL o e n 3 4 4 3

ALLEN 75 5 Correct solubility order is 1 MgF MgCl 2 BaF BaCl 3 LiF LICI 4 Ag 0 Ag S When CuSO is added to a solution of ammonia 76 fol 1 MgF MgCl 3 LiF LICI 2 BaF BaC1 4 Ag 0 Ag S t Char

Select the correct diagram for an endothermic reaction that proceeds through two steps with the second step is rate determining 1 PE 2 PE 3 PE 4 PE Reaction coordinate Reaction coordinate ALLEN Reaction coordinate M 89 Reaction coordinate Addition of catalyst during a chemical reaction 90 En eff qot ar af ferata va n Autres fam 1 PE 2 PE 3 PE 4 PE Reaction coordinate Reaction coordinate Reaction coordinate M Reaction coordinate fat merefte affenf M

Which of the following compound does not give 88 A haloform reaction with alkali and halogen 1 CH C O C H 0 2 CH C CH CI O 3 CH C NH O 4 CH CH OH 2 4

For a first order reaction if the initial concentration of the reactant is 0 8 M and rate constant is 6 93 10 3 s 1 then the rate of the reaction after 100 s will be 1 4 x 10 M s 1 2 5 x 10 2 MS 1 2 8 10 M S 1 1 9 x 10 4 MS 1

4 Cannot predict The pH of a mixture of 100 mL of 0 5 M HC1 47 and 100 mL of 0 6 M NaOH solution is 1 11 3 2 10 3 3 12 7 4 4 3 4 100 ff 0 5 M HCI 100 Ft 0 6 M NaOH facfm pH 1 11 3 2 10 3 3 12 7 4 4 3

Read the graph given below and calculate the threshold frequency and work function for metal used in photoelectric effect from the graph of KE and frequency of incident radiation 3 8 cv T 1 2 ev KE of photoelectron frequency of incident radiation COF 21 10 34

Which one of the following order represent the 84 correct sequence of the increasing basic nature of the given oxides 1 Na O K O MgO Al O 2 K O Na 0 Al 0 MgO 3 Al O MgO Na O K O 4 MgO K O Al O Na O Alfafaa 1 Na O 2 K 0 3 A1 0 4 MgO

Which of following do not gives alcohol with 78 NaBH Tehra to ta NaBH 1 3 J la 2 n b no 3 H Jedn

E of Mg Mg Zn Zn and Fe Fe are 47 2 37V 0 76V and 0 44 V respectively Which of the following is correct 1 Mg oxidizes Zn 2 Zn oxidises Fe 3 Zn reduces Mg 4 Zn reduces Fe Mg Mg Zn Zn e Fe Fefa E 2 37V 0 76V 0 44 V 1 Mg Zn 2 2 Zn Fe 3 3 Zn Mg 4 Zn Fe 1 340 1

9 An ideal solution was obtained by mixing methanol and ethanol If the partial vapour pressure of methanol and ethanol are 2 619 kPa and 4 556 kPa respectively the composition of vapour in terms of mole fraction will be 1 0 635 MeOH 0 365 EtOH 2 0 365 MeOH 0 635 EtOH 3 0 574 MeOH 0 326 EtOH 4 0 173 MeOH 0 827 EtOH

1 8 endothermic reaction energy of activation is E anc enthalpy of reaction is AH both of these in kJ mol Minimum For an value of E will be a less than AH more than AH 17 b equal to AH d equal to zero

During the decomposition of H O2 to give oxygen 48 g 0 2 is formed per minute at a certain point of time The rate of formation c water at this point is 0 75 mol min 1 O 1 5 mol min O 2 25 mol min O 3 0 mol min 1

is provided S A No I E O mol mol mol L L 1 L 1 s 4 x 10 2 O 4x10 2 22 2 x 10 B Rate A 4x10 2 B 8x10 2 o D 8 x 10 No CLEAR SELECTION The correct rate law expression will be 2 OPTIONS MARK FOR REVIEW d B k dt d B dt 2x 10 4 x 10 d B dt K A 2x 10 d B 2 2 0 2 k A B 401 K A B

A vessel initially contains two gases A and B in the mass ratio 2 1 respectively If the above gas mixture is allowed to effuse through a hole then the molar composition of the mixture coming initially out of hole is 1 4 Select correct option s Options The simplest whole number ratio of the moles of gases A and B present in the vessel in the beginning respectively is 1 2 The simplest whole number ratio of the moles of gases A and B present in the vessel in the beginning respectively is 1 8 If the mass ratio of gases A and B required in the final concentrated sample is 1 32 then the number of successive steps of effusion to be carried out is 5 If the mass ratio of gases A and B required in the final concentrated sample is 1 32 then the number of successive steps of diffusion to be carried out is 6

Degeneracy of p orbitals remains unaffected in presence of external uniform magnetic field but degeneracy of d and orbitals is affected by external magnetic field why degeneracy of p orbitals remain unaffected in presence of external magnetic field while degeneracy of d and f get affected

galvanic cell the reactions taking place in the anodic half cell and the cathodic half cell will be 3 Oxidation and reduction 2 Oxidation 4 Reduction and oxidatio Reduction of the following is not true for a galvanic cell represented in IUPAC system

Time required for 99 completion is the time required for the completion of 90 reaction for first order reaction fill in the blank with appropriate option given below O two times Othree times Ofour times

Which among the following statement is not true for rate constant of a reaction Unit of rate constant depend upon the order of reaction b Rate constant depend upon the concentration of the reactants c Rate constant has a definite value at a particular temperature d Rate constant changes with temperature O O b O a C

When the pressure on a gas is decreased to 1 4 and the absolute temperature is in creased four fold the volume of gas Increases by 16 times 2 Decreases to 1 16 3 Increases by 8 times 4 Remains the same

Find the standard cell potential involving the cell reaction 3 In Cu In Cut at 298 K Given EC Cu X V E X V E X V 1 X X3 X2 2 x x3 2x2 3 3 X1 X3 2x2 4 X X3 2x2

cm is chopped lengthwise into 5 equa pieces Then the effective adsorption power Mark for review late Increases by 2 33 times Decreases by 2 33 times Increases by 2 14 times Decreases by 2 14 times

In a solid AB having NaCl structure A atoms occupy the corners and face centre of the cubic unit cell If all the face centred atoms along one of the axes are removed then the resultant stoichiometry of the solid is 1 AB 2 A B 3 A B3 4 A3B4

Which compounds is are not possible for C4H8O A Aldehyde B C D Saturated Alcohol Cyclic ether Ester

for the manufacture of chlorine using mang anese dioxide we do get manganese chlorid e but we also get chlorine gas because the t wo chlorine atoms attract each other and be cause neither of them can lose electrons bu t have equally high electronegativities they t end to attract and this is only because we u sed 4 hydrogen chloride atoms So in other cases we would only get manganese chlori de but not chlorine gas

If iron oxide has formula Feo 950 then what percentage of Fe exist as Fe ion U BIRRA CIGUGG 12 Feo 950 al faxan ufagia Fe Fe YRA 35 QU URI GA OPTIONS MARK FOR REVIEW CLEAR SELECTION OA 85 OB 98 5 OC 89 5

The activation energy for a reaction at the temperature T K was found to be 2 303 RT J mol 1 The ratio of the rate constant to Arrhenius factor is Karnataka CET 2010 A B C 2x10 3 10 1 10 2 C 10 2

the temperature is raised from 300 K to 310 K is log 2 0 3 OPTIONS CLEAR SELECTION MARK FOR REVIEW A 50 6 kJ mol 1 OB 75 45 kJ mol 1 C OC 45 5 kJ mol 1 DI Eo ALLmal 1

For a reaction MM ne A graph is plotted between reduction potential E and log M If at 298K the value of slope is 0 0295 then value of n is 3 2 1 1 2 3 holf reactions for a cell are 4 4

18 V P A C B 1 A 3 C H O D NaCl solution A T Freezing point of solution is marked as up of solute vp of solvent 2 B 4 D

If the molar conductance of 0 04 M solution of weak monobasic acid is 10 S cm mol 1 and at infinite dilution is 500 S cm mol then the dissociation constant of the acid will be 8x10 4 1 6 10 5 X O 2 4 x 10 6

70 For the reaction 2A B the concentration of reactant A changes from 0 04 M to 0 02 M in 2 min The average rate of reaction is 1 0 01 Ms 3 8 33 x 10 Ms1 2 1 66 100 Ms 4 5 10 Ms 1

the solution for 420 minutes Potassium chlorate is prepared by electrolysis of KCI in basic solution as 6OH CI CIO 3H O 6e What time is required to produce 10 g of KCIO using a current of 3 amp

For the reaction N 05 9 2NO g O g the value of rate of disappearance of N O5 is given as 6 25 x 10 3 mol L 1 s 1 The rate of formation of NO2 and O2 is given respectively as CBSE AIPMT 2010 A B C D 6 25 x 10 3 mol L s and 3 125 x 10 3 mol L 1 s 1 6 25 x 10 3 mol L 1 s and 6 25 x 10 3 mol L 1 s 1 6 25 x 10 3 mol L s and 1 6 25 x 10 3 mol L 1 s1 1 25 x 10 2 mol L 1 s and 3 125 x 10 3 mol L 1 s 1

Which of the following statements is are not true 1 Density of solid gets increased due to interstitial defects 2 Frenkel defects do not alter the density of the solid 3 Non stoichiometric defects modify the formula of the compound 4 Non stoichiometric defects do not alter the

3 Without consulting the provided appendix predict whether the entropy change is positive or negative for each of the following reactions Given reasons for your predictions a CH4 g H O g CO g 3H g b C s 0 CO g c H O 1 H L 1 202 g d N g 2N g

The maximum molar conductivities of X 3 and Y ions are 200 and 100 S cm mol respectively The molar conductivity of XY3 at infinite dilution is 1 300 S cm mol 2 150 S cm mol 3 500 S cm mol 4 900 S cm mol

The standard boiling point of A is 400K The enthalpy of vapourisation A at 400 K and 1 bar is 20 kcal mol Which of the following information s is are correct regarding the process A 400K 1 bar A g 400K 0 5 bar Given Cp m values in cal K mol A g 5 A I 10 In 2 0 7 In 5 1 6 Assume ideal behaviour of A g AHM 20 kcal mol O ASM 45 1 cal K mol AGM 560 cal mol The given process is a reversible process

kJ mol to 10 kJ mol 1 The temperature at which uncatalysed reaction will have same rate as that of catalysed at 27 C is OPTIONS CLEAR SELECTION OA 327 C OB 283 C C 445 C MARK FOR REVIEW

in the case of a chemical reaction are 37 5 and 51 3 kJ mole respectively The reaction is OPTIONS CLEAR SELECTION MARK FOR REVIEW OA Endothermic OB Exothermic C Neither exothermic nor endothermic

when OPTIONS MARK FOR REVIEW CLEAR SELECTION OA Concentration of all reactants are unity B Concentration of all reactants and products are equal C Concentration of reactants and products do not change with time