Chemical kinetics Questions and Answers

4 1 5 10 1 The rate of a first order reaction is 0 04 molers at 01 min and 0 03 moles at 0 2 min after start of reaction The rate constant of the reaction is in min approximately 1 1 2 2 91 313 oxy 003 K 9 catalyst lowers the energy of activatio by 25 12 2 9x10 3 10 3 4 1 5 10 20 04 mole 10 2 mole 2 2 3 3 M 313 Mo 0 03 s 1 0 1 se 0502

A 120 g sample of new wood has 21 8 mg of carbon 14 After a period of time there is now 5 45 mg of carbon 14 If the half life of carbon 14 is 5730 years how old is the wood now Select one O a 4 00 years b 22 900 years O c 5730 years d 5 50 years e 11 500 years

13 If initial concentration is reduced to 1 4 is 75 S in a zero 13 feffaf order reaction the time taken for half the reaction to complete is 1 75 S 2 150 S 3 50 S 4 37 5 S ukt 4x K x 75 xt XY 75ffa en tot m 1 75 S 2 150 S 3 50 S 4 37 5 S D 1 22 24 2 Table ld 75 c

lass XIII Spartan Batch Chemical Kinetics GOC 31 In the following reaction A B C rate constant is 0 001 31 37ffshAB C fi 0 001 Ms A 1M 10 FAB Ms If we start with 1 M of A then conc of A and B after 10 minutes are respectively 1 0 5 M 0 5 M 2 0 6 M 0 4 M 3 0 4 M 0 6 M 4 None of these poslas 1 0 5 M 0 5 M 2 0 6 M 0 4 M 3 0 4 M 0 6 M 4 00001 0 Ti jop 0 4 7 99 0

48 A zero order reaction A Product with an initial concentration A has a half life of 0 2 s If one starts with the concentration 2 A o then the half life is a 0 1 s b 0 4 s c 0 2 s d 08s

26 For a reaction A 3B Product Rate d A dt 26 k A 2 B the expression for the rate of reaction in terms of change in the concentration of B d B dt will be 1 k A B 2 k A 3B A 3B pro d A at 3 3k A B 4 1 3 k A B G K A B B 903 dt 3A 3B A B B 1 k A B 2 k A 3B 3 3k A B 4 1 3 k A B Chemical Kinetics GOC 32414 a falu d A dt d B dt 927 Rate of d das at dos 3 1

d 40 The rate of disappearance of Cr Oion at any instant in 40 f3ffl 4 a el c the following reaction Cr O 61 14H 2Cr 31 7H O is 1 55 x 10 2 mol L s The rate of formation of iodine is 1 9 3x10 2Ms 1 2 4 65 x 10 2 MS 1 3 5 0x10 Ms 1 4 250x10 Ms 1 conce of catalyst causes the activation Cr O3 61 14H 2Cr 31 7H O 1 55 x 10 mol L s 1 1 9 3x10 2Ms 2 4 65 x 10 2Ms 1 3 5 0x10 Ms 42 50 x 10 Ms 1 22 ritch and sufferfata uch fufh4 enor 188802 812 4 3r vers

45 The rate constant of a reaction is given by K 2 1 x 10 0 exp 2700 RT Correct statement according to this are 23 1 log Kand will be a straight line with slope 1 T 2 The number of effective collisions are 2 1 x 1010 cm sec 3 Half life of the reaction increases with increas temperature 4 None of these

The Rate constant of a first order reaction A 2B C varies with time as k 3t 1 If the initial concentration of A was 10 mol lit and the reaction ra depends on A what is the approximate concentration of A at t 3s 1 10 mol lit 2 10 mol lit 3 10 mol lit 4 10 5 mol lit

4 None of these 32 For the zero order reaction A B C initial concentration 32 A B C A 0 1 M of A is 0 1 M If A 0 08 M after 10 minutes then it s half life and completion time are respectively 1 10 min 20 min 2 2x 10 3 min 4 10 min 3 25 min 50 min 4 250 min 500 min 3 0 4 M 0 6 M 4 A 0 0 0 07 10 ff of 1 10 min 20 min 2 2 x 10 3 min 4 x 103 min 3 25 min 50 min X 4 250 min 500 min ats is not correct for the 33 fanforfit f A 0 08 M M 844 0 06 22 Da 643 VID us A Bre 0 1 0 1 to n n goog 22

OH 1 2 3 9 For the reaction N 3H 2NH3 AAJ KA TOPPER The rate of change of concentration for hydrogen is 0 3 x 10 Ms The rate of change of concentration of ammonia is 1 0 2 x 104 Ms 2 0 2 x 10 Ms 3 0 1 x 10 Ms 4 0 3 x 10 Ms OH

The redox reaction among the following is JEE Main 2020 1 Reaction of Co H O Cl3 with AgNO3 2 Formation of ozone from atmospheric oxygen in the presence of sunlight 3 Combination of dinitrogen with dioxygen at 2000 K 4 Reaction of H SO with NaOH

For a reaction activation energy E 0 and the rate constant at 200 K is 1 6 x 106 s 1 The rate constant at 400 K will be Given that gas constant R 8 314 J K 1 mol NEET 2019 Odisha 1 3 2 x 106 s 1 2 3 2 x 104 S 1 3 1 6 x 106 S 1 4 16 x 103 S 1

An exothermic chemical reaction proceeds by two stages Reactants stage 2 Intermediate Products The activation energy of stage 1 is 50 kJ mol The overall enthalpy change for the reaction is 100 kJ mol Which diagram could represent the energy level diagram for the reaction a E 200 150 100 c E 50 200 150 stage 1 100 50 R P Progress of reaction R P Progress of reaction 200 150 b E 100 50 P R Progress of reaction 200 150 d E 100 50 Me R Progress of reaction

2 NO g Cl g 2 NOCI g was studied at 10 C The following results were obtained where d C1 dt Rate Initial Rate NO mol L Cl mol L mol L min L 1 in a 0 11 0 11 0 22 What is the rate law 0 17 0 34 0 34 Use k for the rate constant Rate b What is the value of the rate constant L mol 2 Rate constant 0 36 0 71 2 80 min 1

K 2min X g Y g K 30min Z g If decomposition of X g is carried out in sealed flask partial pressure of Y after very l time is 100 mmHg then correct option is are take In2 0 7 A Initial pressure of X was 1600 mmHg 0 7 B minutes required for P to become 400 mmHg 16 C Net rate constant for overall reaction is 1 32 P after half life of reaction is 50 mmHg min

Consider the following reaction 2HI g H g 12 g At 500 K the he equilibrium constant Kp is 0 063 A 1 50 L container at 500 K is initially filled with 0 809 mol of HI and allowed to equilibrate What is the equilibrium concentration of 12 g a 0 54 M b 0 14 M c none of the answers given are correct d 0 090 M e 0 18 M

g and pentane g respectively The value of Excell pentane oxygen fuel cell is 1 1 968 V 2 2 0968 V 3 1 0968 V 4 0 0968 V approximately log 4 0 60 log 5 0 69 1 50 min 2 45 min 3 60 min 4 40 min 2 21 3 mg 3 24 3 mg 4 13 6 mg Contact Number 9667591930 8527521718 for the 127 In producing chlorine through electrolysis 100 W power at 125 V is being consumed How much chlorine per min is liberated ECE of chlorine is 0 367x10 6 kg C 1 17 6 mg 128 A solution containing 10g per dm of urea molecular mass 60g mol is isotonic with a 5 solution of a non volatile solute The molecular mass of this non volatile solute is 1 25g mol 2 300g mol 3 350g mol 4 200g mol 129 For the reaction 2A B 3C D Which of the following does not express the reaction rate 1 d C 3 dt 126 If 60 of a first order reaction was completed in 60 min 1 00 g of non electrolyte solute molar mass 250 mol was dissolved in 51 2 g of benzene If the freezing point 50 of the same reaction would be completed in depression constant K of benzene is 5 12 mol the freezing point of benzene will be lowered by 1 0 4 K 2 0 3 K 3 0 5 K 4 0 2 K 2 3 4 130 d D de d B dt d A 2dt 131 During osmosis flow of water through a semi permeable membrane is 1 from solution having higher concentration only 2 from both sides of semi permeable membrane with equal flow rates 3 from both sides of semi permeable membrane with unequal flow rates 4 from solution having lower concentration only 132 A compound is formed by cation C and anion A The anions form hexagonal close packed hcp lattice and the cations occupy 75 of octahedral voids The formula of the compound is 1 CA3 133 2 C A3 3 C3A 4 C3A4 Following limiting molar conductivities are given as H SO4 K SO4 y Scm mol 1 x Scm mol 1

4 23 C 114 The rate of reaction triples when temperature change from 20 C to 50 C Calculate energy of activation for the reaction 1 28 81 kJ mol 1 2 38 51 kJ mol 1 3 18 81 kJ mol 1 4 8 31 kl mol 1

The reaction A Product follows first order kinetic and the progress of reaction is depicted in the figure In A 2 3 4 10 4 2 10 Time sec Half life of this reaction is approximately A 10 s B 100 s C 500 s D 1000 s

13 The rates of a certain reaction times are as follows Time 0 10 20 30 The reaction is 1 Zero order 3 Second order Rate mole litre sec 2 8 10 2 78 10 2 81 10 2 79 10 2 First order 4 Third order 19

0 98 g H3PO4 is dissolved in 100 mL of a buffer solution pH 5 If the equilibrium concentrations H PO HPO PO and H3PO4 are C C C3 and C4 respectively Find pC pC PC3 po pC log C where i 1 2 3 4 Given For H3PO4 K 10 K 108 K 10

4 2 3 104 104 At the intersection point of two curves nA mB the concentration of B can be given by assume I order A Conc m 1 3 A o m n m A o Time B m 2 A n 4 A n A m n n the fig

For a reaction N O5 Given 2NO d N 05 k N 05 dt d NO dt K N O5 d 0 K3 N 05 dt NI 02 2 The relation between k k and k3 are 1 2k K 4K3 4 1 2 k K K3

nuric The ho 115 The rate constant of a particular reaction has the dimensions of a frequency What is the order of the reaction 1 Zero 2 First 3 Second 4 Fractional

4 Ss ring has a crown shape 30 For a gaseous reaction following data is given AB k 10 e 2 2000 T C D K 10 4 1000 7 The temperature at which k k is 1 1000 K 2 2000 K 3 868 82 K 4 434 2 K

2N O5 4NO O2 the variation of concentra tion of N O5 with time can be expressed by N O5 N O5 o e Kt and K 104 sec If initially 1 mole of N O5 taken calculate i Rate of disappearance of N O at t 10 sec ii Rate of reaction during first 104 sec iii Variation of concentration of NO with time

1 1 3 2 1 6 3 1 9 4 1 12 7 A solution of sucrose Molar mass 342 has been prepared by dissolving 68 4g of sucrose in one k of water K for water is 1 86 K kg mol The freezing point of the solution will be 1 0 684 C 2 0 342 C 3 0 372 C 4 0 186 C The metal extracted by electrolysis of its fused salt is 8

For the elementary reaction MN the rate of disappearance of Mincreases by a factor of 8 upon doubling the concentration of M The order of the reaction with respect to Mis 1 4 2 3 3 2 4 1 Which of the following alcohol s don t does not give white turbidity on treatment with

A2 B2 2AB R O R K A a B b Initial A Initial B R O R r Ms 1 0 2 0 04 0 4 0 04 0 4 0 08 0 2 0 1 0 2 Order of reaction with respect to A2 and B2 are respectively Question Type Single Correct Type 1 2 3 a 1 b 1 a 2 b 0 a 2 b 1

2 AH of a reaction A B C is x kJ and forward reaction has activation energy y kJ The activation energy for the reverse reaction is 1 x y kJ 3 x y kJ 2 y x kJ X y 4 kJ Fincrone twice as fast as the rate constant of a second

3 10 3 a gaseous reaction is given by the expression K A B If the volume of the reaction vessel is suddenly reduced to 1 4th of the initial volume the reaction rate relating to original rate will be 1 1 10 2 1 8 3 8 The rate expression for the reaction NH4CNONH CONH Can be derived from the mechanism 1 NH4CNONHANCO fast ii NH4NCONH3 HNCO fast iii NH3 HNCO K4NH CONH slow Which of the following statement are correct about rate expression 1 2 3 4 d urea k k NH NCO dt k d urea k k NH NCO dt k k d urea k NH NCO dt d dt urea k k The term 4 16 9 dc K K NH NCO k k4 rea 1 in a rate equation refers to the

For a reaction Ea 0 and A 3 2 x 104 s at 300K Then value of rate constant k at 310K would be Question Type Single Correct Type 1 6 4 x 104 S 1 2 3 2 x 104 S 1 3 3 2 x 108 S 1 A 32 x 105 1

Consider the following reaction 2A g 2B g C g For which the rate law is Rate K A and k 0 21 what is the concentration of C when t 40 seconds O 0 029 M O 0 036 M O 0 033 M L mol S Given the initial concentration of A is 0 150 M O 0 042 M hh

34 If 60 of a first order reaction was completed in 60 minutes 50 of the same reaction would be completed in approximately log 4 0 60 log 5 0 69 a 45 minutes c 40 minutes b 60 minutes d 50 minutes

The half life of first order decomposition of NH4NO3 is 2 10 hr at 288 K temperature NH4NO3 aq N O g 2H 0 1 if 8g of NH4NO3 is allowed to decompose The time required for NH4NO3 to decompose 90 and the volume of dry N 0 produced at this point measured at STP ara respectively 1 2 3 4 ct Answer 1 Answer 4 incorrect d to Bookmark List View In English 6 978 hr 2016 L 0 319 hr 2 12 L 0 319 hr 2 016 L 6 978 hr 2 241

A certain organic compound A decomposes by two parallel first order mechanisms A k k If ky k 1 9 and k 1 310 is 1 Calculate the concentration ratio of C to A if an experiment is started with only A and allowed to run for one hour A Answer Your Attempt 0 525 0 62 0 81 Correct answer Rate this ques

4 21 Calculate the rate constant The following data were obtained during the first order thermal decomposition of SO Cl at a constant volume so Cl g SO g Cl g 2 Experiment Time s Total pressure atm 1 0 2 100 alculate the rate of the reaction when total pressure is 0 65 atm 0 5 0 6

1 g of a moist sample of a mixture of KCIO and KCI was dissolved in water and made upto 250 mL 25 mL of this solution was treated with SO to reduced chlorate into chloride and the excess SO was boiled off When the total chloride was precipitated 0 1435 g of AgCl was obtained In another experiment 25 mL of the original solution was treated with 30 mL of 0 2 N solution of FeSO and unreacted FeSO required 37 5 mL of 0 08 N solution of an oxidizing agent for complete oxidation Calculate the molar ratio of chlorate and chloride in the given mixture Fe reacts with CIO according to equation CIO 6Fe 6HCl 6Fe 3H O 3

For a reaction 2A 2B C products with the help of the following table find order with respect to A B C B C A 0 010 0 005 0 010 0 005 0 010 0 010 0 005 0 005 O 3 2 0 O 1 1 0 3 2 1 rate of reaction 0 010 5 x 10 3 0 015 5 x 10 3 0 010 1 x 10 2 0 010 25 10 3

metals is generally a slow electrochemi cal reaction involving many steps These steps in volve electron transfer reactions A particular type of oxidation involve overall first order kinetics with re spect to fraction of unoxidised metal 1 f surface thickness relative to maximum thickness T of oxidised surface when metal surface is exposed to air for con siderable period of time 3 In 1 A Rate law df dt 200 hrs t k 1 f where f of oxide film at time t T thickness of oxide film at t 0 8 A graph of In 1 f vs t is shown in the adjacent figure 41 The time taken for thickness to T X thickness

enzene is 35 The entropy of vaporization or 85 JK mol When 117 g benzene vaporizes at its normal boiling point the entropy change of surrounding is 85 J K 3 85 x 1 55 J K 2 85 x 1 5 J K 4 None of these

reaction N g 3H g under certain conditions of temperature and partial pressure of the reactants the rate of formation of NH is 0 001 kg lit h The rate of conversion of H under the same condition is kg lit h 1 0 001 kg lit h 2 0 0015 kg lit h 1 3 0 00017 kg lit h 4 0 0017 kg lit h 1

16 NO required for a reaction is produced by the decomposition of N O5 in CCl4 as per the equation 2N2O5 g 4NO2 g O2 g The initial concentration of N O5 is 3 00 mol L and it is 2 75 mol L after 30 minutes The rate of formation of No is a 1 667 10 2 mol L min b 4 167 10 mol L min c 2 083 10 3 mol L min d 8 33 10 3 mol L min April 2019

Que 7 In a hypothetical reaction A B taking place at constant temperature and pressure activation energies for forward and backward reactions are 15 and 9 kJ mole respectively If potential energy of A is 10 kJ mol then select correct statement Enthalpy of reaction is 6 kJ Potential energy of B is 16 kJ mole Threshold energy of reaction is 24 kJ Reaction is exothermic

9 The rate constants k and k for two different 2000 T 1000 T reactions are 10 6 e and 10 5 1000 K e 3 3 respectively The temperature at which k k is 1000 a 2000 K b K d 2 303 2000 2 303 K 2008

B A gas at 350 K and 15 bar has molar volume 20 percent smaller than that for an ideal gas under the same conditions The correct option about the gas and its compressibility factor Z is a Z 1 and repulsive forces are dominant b Z 1 and attractive forces are dominant c Z 1 and repulsive forces are dominant d Z 1 and attractive forces are dominant

Which is incorrect in reversible process Question Type Single Correct Type 1 2 3 Work on expansion is maximum Driving force is slightly greater than opposing force System and surrounding are always in thermal equilibrium with each other 4 Total entropy change is positive

Two radioactive nuclides P and Q have half lives of 100 min and 60 min respectively After how much time the ratio of nuclides of P Q will be 2 1 if initially they are in the ratio of 4 3 In2 0 7 In1 5 0 4 O 85 7 min O 7 sec O 0 7 min 7 min

For the first order reaction Tav average life T and T 31 fent enfeffer T siten sar T 50 in the increasing order are 1 T50 Tv T25 2 T T Tav 50 545 3 T T T 50 4 T T T M 1 T0 Tv T av 2 T50 T75 TAV 3 T To T DV 4 T T T75