Chemical Kinetics: MCQs Questions - Test Test 1 Sr.
Questions
Answers
No.
1.
#.
/.
-.
.
Answer: In a reaction, A + B Product, rate is doubled when the concentration of B is doubled, and rate increases by a factor of 8 when the concentrations of both the reactants ( A A and B) are doubled, rate law for the reaction can be written as [CBSE AIPMT 2012] (A) Rate = k[! ["! (B) Rate = k[!#["! (C) Rate = k[!["!# (D) Rate = k[!#["!# In a $ero $ero%o %ord rder er rea react ctio ion n for for e&er e&ery y 1' 1' rise rise of te te*e *era ratu ture re,, Answer: the rate is doubled. If the te*erature is increased fro 1' to 1'', the rate of the reaction will becoe [CBSE AIPMT 2012] (A) - ties (B) 1#8 ties (C) # ties (D) 1# ties 0or a first order reaction () *roducts the concentration Answer: of chanes fro '.12 to '.'# 2 in -'inutes. 3he rate of reaction reaction when the concentration of is '.'1 '.'1 2 is4[AIEEE 2012] (A) 1.5/ 6 1' 7 2in (B) /.-5 6 1'7- 2in (C) /.-5 6 1' 7 2in (D) 1.5/ 6 1'7- 2in 3he 3he act acti& i&at atio ion n ene ener ry y of of a reac reacti tion on at a i& i&en en te* te*er erat atur ure e Answer: 71 is found to be #./'/ R3 9 ol . 3he ratio of rate constant constant to the rrhenius factor is [!rn!t!"! CET 2011] (A) '.1 (B) '.'1 (C) '.''1 (D) '.'# Answer: 3he 3he fol follo lowi win n data data we were re obta obtain ined ed duri durin n the the fir first st orde orderr deco*osition of #() "() + (s) at a constant &olue and at a *articular te*erature. :r. 3ie 3otal *ressure in ;o. Pascal 1. t the end of 1' /'' in #. fter co*letion #'' 71 3he rate constant constant in in is [!rn!t!"! CET 2011] (A) <./ (B) '.' 1''> co* co*le leti tion on of a $er $ero o ord order er reaction is [!rn!t!"! CET 2011] →
→
(B)
(D)
(B)
(A)
(B)
→
.
(A) (B) ak (C)
(D)
5.
8.
(D) 3he rate of a cheical reaction doubles for e&ery 1' rise Answer: of te*erature. If the te*erature is raised by ', the rate of the reaction increases by about [AIEEE 2011] (A) - ties (B) 1' ties (C) #- ties (D) /# ties In the hydrolysis of an oranic chloride in *resence of lare Answer: e?cess of water, Rl + @#A RA@ + @l [#est Ben$!% &EE 2010] (A) 2olecularity and order of reaction both are # (B) 2olecularity is # but order of reaction is 1 (C) 2olecularity is 1 but order of reaction is # (D) 2oecularity is 1 and order of reaction is also 1 Radioacti&ity of a sa*le ($ = ##) decreases <'> after 1' Answer: years. Bhat will be the half%life of the sa*leC [#est Ben$!% &EE 2010] (A) years (B) # years (C) / years (D) 1' years 3he acti&ation enery for a reaction at the te*erature 3 D Answer: was found to be #./'/ R3 9 ol71. 3he ratio of the rate constant to rrhenius factor is EEEEEE. [!rn!t!"! CET 2010] (A) 1'71 (B) 1'7# (C) # 6 1'7/ (D) # 6 1'7# 3ie reuired for 1'' *ercent co*letion of a $ero order Answer: reaction is[!rn!t!"! CET 2010] (A) #ka (B) a#k (C) ak (D) ak 3he concentration of R in the reaction R P was easured Answer: as a function of tie and the followin data is obtained [R! 1.' '.5 '.-' '.1' (olar) t (in) '.' '.' '.1# '.18 3he order of the reaction is [IIT &EE 2010] (A) first (B) second (C) third (D) $ero Answer: Bhich of these chanes with tie for a first%order reactionC [De%'i PMT 2010] . Rate of reaction ". Rate constant . @alf%life (A) only (B) only (C) and " only (D) " and only Furin the kinetic study of the reaction, # + " + F, Answer: followin results were obtained4
(D)
(B)
→
<.
1'.
11.
1#.
1/.
1-.
→
→
(C)
(A)
(C)
(D)
(A)
(B)
Run
[!ol G71
["!ol G71
Initial rate of foration of Fol G71 in71 I '.1 '.1 .' 6 1' 7/ II './ '.# 5.# 6 1'7# III './ '.#.88 6 1'71 IH '.'.1 #.-' 6 1' 7# "ased on the abo&e data which one of the followin is correctC[CBSE AIPMT 2010] (A) rate = k[!# ["!# (B) rate = k[! ["!# (C) rate = k[!# ["! (D) rate = k[! ["! 1.
Answer: (D)
0or the reaction ; #A() #;A#() + A#() the &alue of rate of disa**earance of ; #A is i&en as .# 6 1'7/ ol G7 1 71 s . 3he rate of foration of ;A # and A# is i&en res*ecti&ely as4 [CBSE AIPMT 2010] (A) .# 6 1' 7/ ol G71 s71 and /.1# 6 1' 7/ ol G71 s71 (B) .# 6 1'7/ ol G71 s71 and .# 6 1'7/ ol G71 s71 (C) .# 6 1' 7/ ol G71 s71 and .# 6 1'7/ ol G71 s71 (D) 1.# 6 1'7# ol G71 s71 and /.1# 6 1' 7/ ol G71 s71 →
Chemical Kinetics: MCQs Questions - Test 2 Sr.
Questions
Answers
No.
1.
Answer: onsider the reaction, + 7 l# (a) + @#: (a) :(s) + #@ (a) + #l (a) 3he rate euation for this reaction is, rate = k [l#! [@#:! Bhich of these echaniss isare consistent with this rate euationC [AIEEE 2010] (a). l# + @#: @+ + l7 + l+ + @:7 (slow) l+ + @:7 @+ + l7 + : (fast) (b). @#: @+ + @:7 (fast euilibriu) l# + @:7 #l7 + @+ + : (slow) (A) (a) only (B) (b) only (C) "oth (a) and (b) (D) ;either (a) nor (b) Answer: 3he tie for half life *eriod of a certain reaction Products is 1 h. Bhen the initial concentration of the reactant is #.' ol G 71, how uch tie does it take for its concentration to coe fro '.' to '.# ol G 71, if it is a $ero order reactionC [AIEEE 2010] (A) '.# h (B) 1 h (C) - h (D) '. h 3he tie taken for 1'> co*letion of a first order reaction Answer: is #' in. 3hen, for 1<> co*letion, the reaction will t!"e [#B &EE 200] (A) -' ins (B) ' ins (C) /' ins (D) ' ins 0or a cheical reaction ", the rate of the reaction is # Answer: 6 1'7/ol d7/ s71 when the initial concentration is '.' ol
(A)
→
→
→
→
#.
(A)
→
/.
-.
→
(A)
(B)
.
.
5.
8.
<.
d7/. 3he rate of the sae reaction is 1. 6 1' 7# ol d7/ s7 1 when the initial concentration is '.1 ol d7/. 3he order of the reaction is [!rn!t!"! CET 200] (A) ' (B) / (C) 1 (D) # Answer: (C) 0or the deco*osition of a co*ound " at '' D, the followin data were obtained [!rn!t!"! CET 200] ["! ol d7/ Rate of deco*osition of " in ol d7/ s71 '.#' #.5 6 1' 78 '.-' 11.' 6 1' 78 '.' #-.5 6 1' 78 3he order for the deco*osition of " is (A) ' (B) 1 (C) # (D) 1. 3he rate euation for a reaction4 " is r = D [! °. If the Answer: (D) initial concentration of the reactant is a ol d7/, the half life *eriod of the reaction is [!rn!t!"! CET 200] (A) Da (B) aD (C) #aD (D) a#D Answer: (D) 0or a first order reaction P, the te*erature (3) de*endent rate constant (k) was found to follow the euation →
→
lo k = 7(#''') + .'. 3he *re7e?*onential factor and the acti&ation enery Ja, res*ecti&ely, are [IIT &EE 200] (A) 1.' 6 1' sK1 and <.# k9olK1 (B) .' sK1 and 1. k9olK1 (C) 1.' 6 1' sK1 and 1. k9ol K1 (D) 1.' 6 1' sK1 and /8./ k9ol K1 Answer: (C) 0or the reaction + " *roducts, it is obser&ed that (i) An doublin the concentration of only, the rate of reaction is also doubled. (ii) An doublin the initial concentration of both and ", there is chane by a factor of 8 in the rate of reaction. 3he rate of reaction is i&en by [CBSE AIPMT 200] (A) rate = k [! ["! (B) rate = k [!# ["! (C) rate = k [! ["! # (D) rate = k [!# ["!# Answer: (D) →
0or the reaction, ; # + /@#
1'.
#;@/, if
→
= # 6 1'7- ol
G71s71, the &alue of 7 would be [CBSE AIPMT 200] 771 71 (A) - 6 1' ol G s (B) 6 1'7- ol G71 s71 (C) 1 6 1'7- ol G71 s71 (D) / 6 1'7- ol G71 s71 @alf life *eriod of a first order reaction is 1/8 seconds. 3he Answer: (B)
11.
s*ecific rate constant of the reaction is [CBSE AIPMT 200] (A) '. 6 1' 7# s71 (B) '. 6 1' 7/ s71 (C) .' 6 1' 7# s71 (D) .' 6 1'7/ s71 In the reaction "rA/7 (a) + "r7 (a) + @+ /"r# (l) + /@#A(l) 3he rate of a**earance of broine ("r#) is related to the rate of disa**earance of broide ions as [CBSE AIPMT 200]
Answer: (D)
→
(A) (B) (C)
1#.
1/.
1-.
(D) 3he half life *eriod of a first order cheical reaction is . of the cheical reaction will be (lo # = './'1) [AIEEE 200] (A) #/'./ inutes (B) #/.'/ inutes (C) -.' inutes (D) -'. inutes Lnder the sae reaction conditions, initial concentration of Answer: (A) 1./8 ol d7/ of a substance becoes half in -' seconds and #' seconds throuh first order and $ero order kinetics
res*ecti&ely. Ratio of the rate constants for first order (k1) and $ero order (k') of the reaction is [IIT &EE 200] (A) '. ol71 d/ (B) 1.' ol71 d7/ (C) 1. ol d7/ (D) #.' ol71 d7/ 3he broination of acetone that occurs in acid solution is Answer: (D) re*resented by the euation @/A@/(a) + "r#(a) @/A@#"r(a) + @+(a) + "r7 (a) 3hese kinetic data were obtained fro i&en reaction concentrations. [CBSE AIPMT 200] Initial concentrations, (2) [@/A@/! ["r#! [@+! './' '.' '.' './' '.1' '.' './' '.1' '.1' '.-' '.' '.#' Initial Rate, disa**earance of "r#, 2s71 .5 6 1' 7 .5 6 1' 7 1.# 6 1' 7/.1 6 1' 7"ased on these data, the rate of reaction is →
1.
(A) rate = k [@/A@/! ["r#! (B) rate = k [@/A@/! ["r#! [@+!# (C) rate = k[@/A@/!["r#! [@+! (D) rate = k[@/A@/! [@+! 3he rate constants k1 and k# for two different reactions are Answer: (C) 1'1 ⋅e7#'''3 and 1'1 ⋅ e71'''3, res*ecti&ely. 3he te*erature at which k1 = k# is [CBSE AIPMT 200] (A) (B) #''' D (C) (D) 1''' D
Chemical Kinetics: MCQs Questions - Test 3 Sr.
Questions
Answers
No.
1.
Answer: (D)
0or a reaction4 #", rate of disa**earance of is related to the rate of a**earance of " by the e?*ression4 [AIEEE 200] →
(A) (B) (C)
#.
(D) Bhich one of the followin is a second order reactionC [!rn!t!"! CET 200*] (A) @/AA@/ + ;aA@ @/AA;a + @#A
Answer: (A)
→
(B) @# + l# #@l (C) ;@-;A/ ;# + /@#A (D) @# + "r# #"@r Answer: (D) onsider a reaction, aM + b@ Products. Bhen concentration of both the reactants M and @ is doubled, the rate increases by eiht ties. @owe&er, when the concentration of M is doubled kee*in the concentration of @ fi?ed, the rate is doubled. 3he o&erall order of the reaction is4 [IIT &EE 200*] (A) ' (B) 1 (C) # (D) / Answer: (A) If '> of a first order reaction was co*leted in ' inutes, '> of the sae reaction would be co*leted in a**ro?iately [CBSE PMT 200*] (A) - inutes (B) ' inutes (C) -' inutes (D) ' inutes →
→
/.
-.
→
.
In a first order reaction ", if k is rate constant and initial concentration of the reactant is '. 2, then the half%life is [CBSE PMT 200*] →
Answer: (C)
(A) (B) (C)
.
(D) Answer: onsider the reaction, # + " Products Bhen concentration of " alone was doubled, the half%life did not chane. Bhen the concentration of alone was doubled, the rate increased by two ties. 3he unit of rate constant for this reaction is4 [AIEEE 200*] (A) no unit (B) ol G71 s71 (C) s71 (D) G ol71 s71 3he eneries of acti&ation for forward and re&erse reactionsAnswer: for #+ "# #" are 18' k9 ol71 and #'' k9 ol7 1 res*ecti&ely. 3he *resence of a catalyst lowers the acti&ation enery of both (forward and re&erse) reactions by 1'' k9 ol71. 3he enthal*y chane of the reaction (# + "# #") in the *resence of catalyst will be (in k9 ol7 1 )4 [AIEEE 200*] (A) 1#' (B) #8' (C) #' (D) /'' Answer: 0or a reaction + " + F if the concentration of is doubled without alterin the concentration of ", the rate ets doubled. If the concentration of " is increased by nine ties without alterin the concentration of , the rate ets tri*led. 3he order of the reaction is[!rn!t!"! CET 200+] (A) # (B) 1 (C) /# (D) -/ Answer: onsider the reaction4 ;#($) + /@#($) #;@/($)
(D)
→
5.
(C)
→
8.
<.
→
→
3he euality relationshi* between is [CBSE AIPMT 200+] (A) + (B) + (C) +
(C)
(A)
1'.
(D) + 0or the reaction4 # + " / + F Bhich of the followin does not e?*ress the reaction rateC [CBSE AIPMT 200+] →
Answer: (D)
(A) (B) (C)
11.
1#.
1/.
(D) reaction was found to be second order with res*ect to concentration of carbon ono?ide. If the concentration of carbon ono?ide is doubled, with e&erythin else ke*t the sae, the rate of reaction will [AIEEE 200+] (A) tri*le (B) increase by a factor of (C) double (D) reain unchaned Rate of a reaction can be e?*ressed by rrhenius euation as4 k = e7JR3 In this euation, J re*resents [AIEEE 200+] (A) the enery below which collidin olecules will not react. (B) the total enery of the reactin olecules at a te*erature, 3. (C) the fraction of olecules with enery reater than the acti&ation enery. (D) the enery abo&e which all the collidin olecules will react. 3he followin echanis has been *ro*osed for the reaction of ;A and "r# to for ;A"r ;A($) + "r#($) ;A"r#($) ;A"r# () + ;A() #;A"r() If the second ste* is rate deterinin ste*, the order of the reaction with res*ect to ;A() is [AIEEE 200+] (A) ' (B) / (C) # (D) 1 0or the reaction + " , it is found that doublin the concentration of increases the rate by - ties, and doublin the concentration of " doubles the reaction rate. Bhat is the o&erall order of the reactionC [!rn!t!"! CET 200,] (A) (B) /# (C) / (D) 1 Bhich of these does not influence the rate of reactionC [!rn!t!"! CET 200,] (A) ;ature of the reactants (B) oncentration of the reactants
Answer: (B)
Answer: (A)
Answer: (C)
→
1-.
1.
→
Answer: (C)
Answer: (D)
(C) 3e*erature of the reaction (D) 2olecularity of the reaction
Chemical Kinetics: MCQs Questions - Test 4 Sr.
Questions
Answers
No.
1.
#.
/.
-.
.
.
5.
Answer: Bhich of the followin stateents for order of reaction is not correctC [IIT &EE 200,] (A) Arder can be deterined e?*erientally (B) Arder of a reaction is eual to the su of the *ower of concentration ters in differential rate law (C) It is not affected with the stoichioetric coefficients of the reactants (D) Arder cannot be fractional Answer: 3he rate of reaction between two reactants and " decreases by a factor of - if the concentration of reactant " is doubled. 3he order of reaction with res*ect to reactant " is [CBSE AIPMT 200,] (A) # (B) 7# (C) 1 (D) 71 Answer: reaction in&ol&in two different reactants can ne&er be [AIEEE 200,] (A) Lniolecular reaction (B) 0irst order reaction (C) :econd order reaction (D) "iolecular reaction Answer: onsider an endotheric reaction, N O with acti&ation eneries Jb and Jf res*ecti&ely for the backward and forward reactions, res*ecti&ely. In eneral, [AIEEE 200,] (A) Jb Jf (B) Jb Q Jf (C) Jb = Jf (D) there is no definite relation between Jb and Jf t1- can be taken as the tie taken for the concentration of Answer: a reactant to dro* to /- of its initial &alue. If rate constant for a first order reaction is k, then t1- can be written as [AIEEE 200,] (A) '.'1k (B) '.#<k (C) '.<k (D) '.5k Answer: follows first order reaction, () *roduct oncentration of , chanes fro '.1 2 to '.'# 2 in -' inutes. 0ind the rate of reaction of when concentration of is '.'1 2. [IIT &EE 200-] (A) 1.5/ 6 1' 7- 2 in71 (B) /.-5 6 1'7 2 in71 (C) /.-5 6 1' 7- 2 in71 (D) 1.5/ 6 1'7 2 in71 Answer: 3he rate of a first order reaction is 7# 71 71 1. 6 1' ol G in at '. 2 concentration of the reactant. 3he half life of the reaction is [CBSE AIPMT 200-] →
→
(D)
(B)
(A)
(A)
(B)
(C)
(A)
8.
<.
(A) #/.1 in (B) 8.5/ in (C) 5./ in (D) './8/ in In a first order reaction, the concentration of the reactant Answer: decreases fro '.8 2 to '.- 2 in 1 inutes. 3he tie taken for the concentration to chane fro '.1 2 to '.'# 2 is [AIEEE 200-] (A) 5. in (B) 1 in (C) /' in (D) ' in Answer: 3he rate euation for the reaction4 # + " is found to be4 rate = k [! ["!. 3he correct stateent in relation to this reaction is that the [AIEEE 200-] (A) units of k ust be s 71 (B) t1# is constant (C) rate of foration of is twice the rate of disa**earance of (D) &alue of k is inde*endent of the initial concentration of and ". 3he &elocity constant of a reaction at #<' D was found to Answer: be /.# 6 1' 7/ :71. Bhen the te*erature is raised to /1' D, it will be about4 [!rn!t!"! CET 200-] (A) <. 6 1' 7/ (B) 1.#8 6 1'7# (C) .- 6 1' 7/ (D) /.# 6 1' 7Answer: 3he reaction4 " follows first order kinetics. 3he tie taken for '.8 ol of to *roduce '. ol of " is 1 hour. Bhat is the tie taken for con&ersion of '.< ol of to *roduce '.5 ol of "C [CBSE AIPMT 200] (A) 1 hour (B) '. hour (C) '.# hour (D) # hour 3he rate law for a reaction between the substances an " Answer: is i&en by Rate = k [!n ["! An doublin the concentration of and hal&in the concentration of ", the ratio of the new rate to the earlier rate of reaction will be[AIEEE 200] (A) + n (B) n 7 (C) #(n 7 )
(C)
(D)
→
1'.
11.
1#.
1/.
1-.
→
(B)
(A)
(C)
(D) In res*ect of the euation D = e7Ja R3 in cheical kinetics, Answer: (C) which one of the followin stateents is correctC [AIEEE 200] (A) k is euilibriu constant (B) is adsor*tion factor (C) Ja is enery of acti&ation (D) R is Rydbers constant Answer: (A) Lnits of rate constant of first and $ero order reactions in ters of olarity 2 unit are res*ecti&ely [AIEEE 2002] (A) sec71, 2sec71
1.
(B) sec71, 2 (C) 2sec71, sec71 (D) 2, sec71 Bhen a bio cheical reaction is carried out in laboratory out side the huan body in the absence of en$ye, then the rate of reaction obtained is 1' 7 ties, than acti&ation enery of reaction in the *resence of en$ye is4 [AIPMT 2001] (A) R3 (B) P is reuired (C) Fifferent fro, Ja obtained in laboratory (D) ant say any thins
Answer: (C)
