Chemical kinetics Questions and Answers

22 For a reaction of the type A B products it is observed that doubling the concentration of A causes the reaction rate to be four times as great but doubling the amount of B does not effect the rate The rate equation is 1 Rate K A B 3 Rate K AB 2 Rate K A 4 Rate K APIB CK0024 de 8 1 29 TE FOUNG or 1 2 3

CK0023 2 22 For a reaction of the type A B products it is observed that doubling the concentration of A causes the reaction rate to be four times as great but doubling the amount of B does not effect the rate The rate equation is 1 Rate K A B 2 Rate K A 3 Rate KAPIB 4 Rate KIA B 2

Following graph represents variation of half life period t 2 of a nth order reaction with A initial concentration of the reactant 1 12 A Order of reaction may be 0 1 02 01 1 2 Zoro

21 The rate law for the single step reaction 2A B 2C is given by 1 Rate K A B 2 Rate KAIBI 3 Rate K 2A B 4 Rate KIA B

26 For the reaction A B products it is found that the order of A is 1 and the order of B is When the concentration of both A and B are increased four times the rate will increase by a factor of 1 16 3 6 4 4 2 8

Which among the following is a first order reaction O 2 NH3 g O O g O 2H O 1130K Pt catalyst N g 3 H g 2NO g 10 g 2 1 alkaline medium O 2 NO g O g 2 NO g 2H O O

Pre Medical Chemistry 59 16 Select the rate law that corresponds to the data shown for the following reaction A B C Exp A 1 0 012 2 0 024 3 0 024 4 0 012 1 Rate K B 3 Rate m K A B B Initial rate 0 10 0 035 0 070 1 6 0 035 0 20 0 070 0 80 2 Rate K B 4 Rate KIABJ CK0016

6 Rate of formation of SO according to the reaction 2SO O 250 is 1 6x10 kg L min Hence rate of decomposition of SO is 1 1 6 x 10 2 8 0 x 10 3 3 2 x 10 4 1 28 x 10 kg L min kg L min kg L min kg L min CK0006

For the reaction N O 2NO 20 d N 05 dt Given d0 1 dt K N O51 NO KINO dt KINOI The relation between K K and K is 1 2K K 4K 2 K K K 3 2K 4K K 4 None CK0005

CK0001 In the formation of sulphur trioxide by the contac process 2SO g O g 2SO g the rate o reaction is expressed as d 0 2 5 x 10 mol L s dt The rate of disappearance of SO will be 1 5 x 104 mol L s 2 2 25 x 104 mol L s 3 3 75 x 104 mol L s 4 50 0 x 104 mol L st

50 During 2A B Run the kinetic study of the reaction C D following results were obtained A mol L 1 B mol L 1 Initial rate of formation of D mol L min 1 0 1 II 0 3 III 0 3 N 0 4 I 0 1 0 2 0 4 0 1 2 1 rate k A B 3 rate k A B 6 0 10 3 7 2 x 10 2 2 88 x 10 1 2 40 10 Based on the above data which one of the following is correct 2 rate K A B 4 rate k A B

RATE LAW ORDER MOLECULARITY 10 For gaseous reaction ratek A B If volume of container is reduced to of initial then the 1 rate of the reaction will be times of initial 2 8 4 16 100 3 16

1 2A B Product is an elementary reaction If pressure of both A and B is increased three times of the initial pressure the rate of forward reaction will be of the previous rate 1 9 times 2 27 times 4 2 7 times 3 times The ra of certain hunothe CK0011

60 20 Pre Medical Chemistry For a chemical reaction A B is one with respect to each A and B Value of x and y from the given data is JAJ Rate mol L s 0 10 0 40 0 80 1 0 20 0 80 3 0 80 0 20 0 20 M X 0 40 M product the order 26 B 0 05 M 0 05 M y 2 0 80 0 40 4 0 40 0 20 27

and 1 Consider the reaction N g 3H g 2NH g The correct equality relationship between d H dt 2 3 dt 4 dt d NH 1 d H dt 3 dt 3 d NH 2 d H 3 dt dt d NH 3 d H dt 2 dt d NH d H dt 2 dt CK0117 dNH dt RED LO STRONORS R

Which one is the correct graph for zero order reaction where R is the concentration of reactant O Rate Rate R R Rate R 4 2 Rate R

eaction 2N O5 9 2N O4 g O g If initial pressure of N O5 is 2 atm then total pressure at t t 2 is Options 1 atm 5 2 atm 3 atm 6 atm Solution

3 2r 31 For the reaction 2A B 3C D Which of the following does not express the reaction rate 1 d C 2 3 dt d B dt 3 CK0007 d D 1d A 4 dit 2 dt

For a hypothetical reaction A B C the following data were obtained in three different experiments B A mol L moll mol L 0 01 0 01 0 01 0 03 0 03 0 03 The rate law will be 1 r K AB 3 r KIA B Rate of reaction mol L min 1 0x10 9 0x101 2 70x10 2 r K A B 4 None of these CKOOL

18 The reactions having very high values of energy of activation are generally A Very slow B Very fast C Spontaneous D Medium fast 19 For a first order reaction K 10 3 min its t A 3300 min B 2000 min C 1500 min D None of the three 20 For which reaction the collision theory is generally more satisfactory A First order B Second order C Zero order D Any order 21 In the reaction AB if the concentration of A is doubled then the reaction rate increases by 1 59 times then what will be the order of reaction

In a first order reaction A P the ratio of a a x was found to be 8 after 60 min If the concentration is 0 1 M then the rate of reaction is 1 2 226 103 mol L min 2 3 466 10 mol L min 3 4 455x10 mol L min 4 5 532x10 mol L min

3 T 27 3 K 4 T 273 K 2 At a given temperature equilibrium is attained when 50 of each reactant is converted into the products A g Bg C g Dg If amount of B g is doubled percentage of B converted into products will be 1 100 2 50 3 66 67 4 33 33

For the reaction 2NO g O g 2NO g On doubling the concentration of NO while keeping the concentration of O constant The initial rate increases by a factor of four The order with respect NO g is Options 0 1 2 3 Solution

90 The pH of solution is increased from 3 to 6 Its H ion concentration will be 1 Reduced to half 2 Doubled 3 Reduced by 1000 times 4 Increased by 1000 times UURIUM 02 EXEP65

For a first order reaction the time required for 99 9 completion is 100 min What will be the rate constam for the reaction 1 25 x 10 4 S 1 1 15 x 10 3 1 2 2 x 10 S 1 4 5 x 10 S 1

For an elementary reaction k 2A 3B 2C The rate of dissappearance of B is k Question Type Single Correct Type 1 k A B K C 2 3k A B 3k C 3 2k A 2 B 3 2k C 4K A B K C

Dimerisation of NO2 is an exothermic reaction If enthalpy of reaction is AH then the minimum value of activation energy for forward reaction E will be O Equal to AH O Equal to zero O Greater than AH O Greater than threshold energy

For the reaction 2 N O5 4 NO2 O2 rate of reacti is given by O 1 d N 05 2 dt 2d 05 dt O d NO dt min se d 0 dt

represented by dots in the graph The plotted lines are isotherms Order of the most probable speed v of the molecules at these five states is M 1 Vp at 3 2 Vp at 1 Vp at 1 Vp at 2 Vp at 41 pat 5 Vp at 2 Vp at 3p at 4 Vp at 5 1 Vp at 3 Vp at 1 2 Vp at 1 Vp at 2 Vpat 2 pat 3 pat 4 Exam at 5 at 5

4 moles of A are mixed with 4 moles of B when 2 mol of C are formed at equilibrium according to the reaction A B C D The equilibrium constant is 1 4 2 1 3 2 2005E

A solution containing 0 01 M Zn and 0 01 M Cu is saturated by passing H S gas The S concentration is 8 1 x 102 M K for ZnS and CuS are 3 0 x 10 22 and 8 0 x 10 respectively Which of the following will occur in the solution 1 ZnS will precipitate p 2 CuS will precipitate 3 Both ZnS and CuS will precipitate 4 Both Zn and Cu will remain in the solution

How why rate of reaction is independent of molecularity o f reaction 3 Rate of chemical reactions is independent of molecularity of reactions

EXERCISE I Conceptual Questions FACTORS AFFECTING RATE OF REACTION 1 In an elementary reaction A 2B 2C D If concentration of A is increased four times and I decreased to half of its initial concentration th the rate becomes 1 Twice 2 Half 3 Unchanged

LAW OF MASS ACTION In a chemical equilibrium the rate constant for the backward reaction is 7 5 x 104 and the equilibrium constant is 1 5 The rate constant for the forward reaction is 1 2x10 1 2 5 x 10 4 3 1 12 x 10 3 4 9 0 x 10 4 AL EGULBRAM02 EXEP65

The rate constant for a second order reaction is 8x10 5 M min How long will it take a 1M solution to be reduced to 0 5M 1 8 665 x 10 minute 2 8 x 10 5 minute 3 1 25 x 104 minute 4 4x10 5 minute

S0028 1 g and nded by 34 between ilibrium 3 it is zero at all points 4 1 and 2 both ession 20201 1 Which one of the following pattern of electrostatic lines of force is not possible ES0032 2

3 A solid sphere of radius R is charged uniformly with a total charge Q Then the correct expression for electric field is r distance from centre KQr R where r R KQ 2 where r 2 R ES0031 3 it is zero at all points 4 1 and 2 both

For acid catalysed hydrolysis of ester rate constant is given as 7 in Vx V K In where Vo V and V are volume of standard NaOH solution required to neutralise acid present at given time If ester gets 50 hydrolysed then O V V O Vx V Vo O Vx 2V Vo O V 2V 2V0

37 For an elementary reaction k 2A 3B 3B k dissappearance of B is 2C The rate of 1 k A B k C 2 3k A B 3k C 3 2k A B 2k C 4 A B k C

chanism of a X Y 2XY is given below 1 X X X ii X Y XY Y slow iii X Y XY fast The overall order of the reaction will be NEET 2017 1 1 3 O 0 hypothetical reaction 2 2 4 1 5

A 7 5 x 10 3 B 6 2 x 10 8 C 4 8 x 10 13 D 10 19 Acid Name Phosphoric Arsenic Carbonic Sulfuric Sulfurous U Formula H PO4 H AsO 4 H CO3 H SO4 H SO3 N Kal 7 5 x 10 5 x 10 4 3 x 10 7 large 1 5 x 10 K 2 6 2 x 10 8 8 x 10 8 5 6 x 10 11 1 2 x 10 1 0 x 10 7 Ka3 4 8 x 10 13 6 0 x 10 10

One liter of 0 5 M KCI solution is electrolyzed for one minute in a current of 1 608 mA Considering 100 efficiency the pH of the resulting solution will be 1 7 2 9 3 8

Enter your answer in the provided box The rate constant for the second order reaction 2NOBr g 2NO g Br g is 0 80 Ms at 10 C Starting with a concentration of 0 86 M calculate the concentration of NO after 91 s 1 M

elementary reaction 2AB the rate of disappearance of A is equal to 2k k 2 2k A 2k B 3 2k A 2k B 4 2k k A 1 A

For the reaction 2A B C with the rate law d C k A B and started with A and B i dt stoichiometric proportion Which is are true unit of k is MS 1 A B and C all will be linear functions of time C 2kt D C kt

The figure given below shows three velocity substrate concentration curves for an enzyme reaction What do the curves A B and C depict respectively Initial velocity V A B C Substrate concentration S A A normal enzyme reaction B competitive inhibition C non competitive inhibition Correct Answer B A enzyme with an allosteric modulator added B normal enzyme activity C

las constant of decomposition of methyl nitrite and ethyl nitrite are VI 008 1 1 k s 10 3 exp 152300 Jmol RT 157700 Jmol and k s 10 4 exp 19 respectively The temperature at which the rato constants and equal is RT

36 The heat of neutralisation of HCl by NaOH is 55 kJ mol If the heat of neutralisation of HCN by NaOH i 12 1 kJ mol The energy of dissociation of HCN is a 43 8 kJ c 68 kJ b 43 8 kJ d 68 kJ When a certain amor 37

The specific conductance of saturated solution of CaF2 is 3 86 x 10 5 mho cm 1 and that of water used for solution is 0 15 x 10 5 The specific conductance of CaF2 is 3 71x10 4 3 86 10 4

At substrate concentration S rate of the reaction V is a quarter of Vmax What is Km in terms of S ADDHAL ALIE Problem 16 At substrate concentration S rate of the reaction V is a quarter of Vma What is K in terms of S