MHT-CET 2008
1 . After how many seconds will the concentration of the reactant in a first order reaction be halved if the rate constant is 1.155 x 10^-3 s^-1
- (A) 600
- (B) 100
- (C) 60
- (D) 10
MHT-CET 2009
2. Which is a correct integrated rate equation?
- (A) k = -2.303/t log a/(a - x)
- (B) k = -2.303/t log (a - x)/a
- (C) -d (a - x) = k dt
- (D) All are integrated rate equations
3. For which order reaction, the unit of rate constant is time^-1 ?
- (A) Zero order
- (B) First order
- (C) Second order
- (D)Third order
MHT-CET 2010
4. The units of rate constant for first order reaction are
- (A) mol L-1 s-1
- (B) s-1
- (C) L mol-1 s-1
- (D) L² mol-2 s-1
- (A) k = x/t
- (B) k = -2.303/t log a/(a-x)
- (C) k = 1/t ln a/(a-x)
- (D) k = 1/t x/a(a-x)
6. In a multistep reaction, the overall rate of reaction is equal to the
- (A) rate of slowest step
- (B) rate of fastest step
- (C) average rate of various steps
- (D) the rate of last step
- (A) 342 kJ mo1-1
- (B) 269 kJ mol-1
- (C) 34.7 kJ mol-1
- (D) 15.1 kJ mol-1
8. Rate law for the reaction A + B → product is rate = k [A]2 [B]. What is the rate constant if the rate of reaction at a given temperature is 0.22 Ms-1. when [A] = 1M and [B] = 0.25 M?
- (A) 3.52 M-2s-1
- (B) 0.88 M-2s-1
- (C) 1.136 M-2s-1
- (D) 0.05 M-2s-1
9. For the reaction O3(g) + O(g) → 2O2(g) if the rate law expression is, rate = k [O3] [O] the molecularity and order of the reaction are respectively
- (A) 2 and 2
- (B) 2 and 1.33
- (C) 2 and 1
- (D) 1 and 2
- (A) t1/2 = [A]02kt
- (B) t1/2 = 0.693/k
- (C) t1/2 = [A]0 /2k
- (D) t1/2 = 2[A]0/k
- (A) 1.596 h-1
- (B) 0.1 h-1
- (C) 4.802 h-1
- (D) 10 h-1
12. The reaction takes place in two steps as
i) NO2C(g) → NO2(g) + Cl(g) ii) NO2Cl(g) + Cl(g) → NO2(g) + C12(g) Identify the reaction intermediate.
- (A)NO2Cl(g)
- (B) NO2(g)
- (C) Cl2(g)
- (D) Cl(g)
- (A) t1/2 = 0.693/k
- (B) t1/2 = 0.693 k
- (C) k = 0.693 t1/2
- (D) kt1/2 = 1/0.693
- (A) △[SO2]/△t
- (B) -△[O2]/△t
- (C) 1/2△[SO2]/△t
- (D) △[SO3]/△t
15. Which among the following reactions is an example of pseudo first order reaction?
- (A) Inversion of cane sugar
- (B) Decomposition of H2O2
- (C) Conversion of cyclopropane to propene
- (D) Decomposition of N2O5
- (A) k = A.eEa/RT
- (B) k = A.eRT/Ea
- (C) k = A/eEa/RT
- (D) k = A/eRT/Ea
17. The
rate constant for a first order reaction 7.0 x 10^-4 s^-1. If initial
concentration of reactant is 0.080, what is the half-life of reaction?
- (A) 990 s
- (B) 79.2 s
- (C) 12375 s
- (D) 10.10 x 10^-4
18. A certain reaction occurs in two steps as
i) 2SO2(g) + 2NO2(g) → 2SO3(g) + 2NO(g) ii) 2NO(g) + O2(g) → 2NO2(g)
in the reaction,
- (A) NO2(g) is intermediate
- (B) NO(g) is intermediate
- (C) NO(g) is catalyst
- (D) O2(g) is intermediate
- (A) -Ea
- (B) -2.303 Ea/R
- (C) -Ea/2.303 R
- (D) -Ea/R
20. For the elementary reaction 2SO2(g) + O2(g) → 2SO3(g), identify the correct among the following relations:
- (A) +d[SO3(g)]/dt = -2d[O2(g)]/dt
- (B) +d[SO2(g)]/dt = -d[O2(g)]/dt
- (C) +1/2d[SO3(g)]/dt = d[SO2(g)]/dt
- (D) -d[SO2(g)]/dt = -d[O2(g)]/dt
21. Which among the following reaction is an example of a zero order reaction?
- (A) 2NH3 → N2(g) + 3H2
- (B) C12H22O11(aq.) + H2O(l) → C6H12O6(aq.) + C6H12O6(aq.)
- (C) H2(g) + I2(g) → 2HI(g)
- (D) 2H2O2(l) → 2H2(l) + O 2(g)
- (A) 1.6 x 10^-6 s^-1
- (B) 1.6 x 10^-5 s^-1
- (C) 3.2 x 10^-6 s^-1
- (D) Zero
- (A) increases by a factor of 4
- (B) increases by a factor of 3
- (C) increases by a factor of 8
- (D) increases by a factor of 2
- (A) -3/2d[H2(g)]/dt = d[NH3(g)]/dt
- (B) d[NH3(g)]/dt = -1/3 d[H2(g)]/dt
- (C) -2/3d[H2(g)]/dt = d[NH3(g)]/dt
- (D) -[H2(g)]/dt = d[NH3(g)]/dt
26. Order of which among the following reactions is NOT one?
- (A) 2H2O2(l) → 2H2O(l) + O2(g)
- (B) Cyclopropane → CH3 -- CH == CH2(g)
- (C) 2N2O5(g) → 2NO2(g) + O2(g)
- (D) CHCl3(g) + Cl2(g) → CCl4(g) + HCl(g)
- (A) 2
- (B) 1.5
- (C) 1
- (D) 0
- (A) rate = k[A]2 [B]
- (B) rate = k[A] [B]2
- (C) rate = k[A]2 [B]2
- (D) rate = k[A] [B]
- (A) 9.605 x 10^-2 min^-1
- (B) 3.465 x 10^-3 min^-1
- (C) 1.374 x 10^-3 min^-1
- (D) 288.6 min^-1
- (A) 3A + 2B → C
- (B) 2B → 3A + C
- (C) 2B + C → 3A
- (D) 3A → 2B + C
- (A) 9 x 10^-5 s^-1
- (B) 9 x 10^-4 s^-1
- (C) 1.1 x 10^-4 s^-1
- (D) 1.1 x 10^-5 s^-1
32. Which of the following is a character of catalyst?
- (A) It increases the rates of both forward and backward reactions equally in reversible reaction
- (B) It increases the activation energy of reactants
- (C) It affects the energies of reactants and products of the reaction
- (D) It changes the position of equilibrium
- (A) 0.0133 M/s
- (B) 0.004 M/s
- (C) 0.032 M/s
- (D) 0.023
- (A) e-Ea/RTdecreases
- (B) -Ea/RT decreases
- (C) K decreases
- (D) Ea/RT decreaces
- (A) 66.56 min
- (B) 6.6 min
- (C) 150 min
- (D) 79.68 min
among the following is correct?
- (A) The reaction is first order in O2, first order in NO and second order overall
- (B) The reaction is second order in NO, zero order in O2 and second order overall
- (C) The reaction is second order in NO, first order in O2 and third order overall
- (D) The reaction is zero order overall
- (A) 5/0.693 min^-1
- (B) 0.693/15 min^-1
- (C) 0.693 x 5 min^-1
- (D) 0.693/5 min^-1
- (A) 10.42 h
- (B) 9.51 h
- (C) 30.36 h
- (D) 4.25 h
- (A) 0.25 s^-1
- (B) 0.30 s^-1
- (C) 2.25 s^-1
- (D) 0.075 s^-1
40. For
the reaction 4NH3 + 5O2 → 4NO + 6H2O, the rate of disappearance of NH3
is 3.6 x 10^-3M/s. What is the rate of formation of water?
- (A) 6.0 x 10^-4 M/s
- (B) 5.4 x 10^-3 M/s
- (C) 3.6 x 10^-3 M/s
- (D) 4.0 x 10^4 M/s
- (A) 3
- (B) 1
- (C) 2
- (D) 0
- (A) 7.75 x 10^-4 mol L^-1 s^-1
- (B) 8.15 x 10^-4 mol L^-1 s^-1
- (C) 4.96 x 10^-4 mol L^-1 s^-1
- (D) 2.01 x 10^-4 mol L^-1 s^-1
- (A) 62.12 min
- (B) 38.31 min
- (C) 48.12 min
- (D) 12.77 min
- (A) Hydrolysis of CH3COOCH3
- (B) inversion of C12H22O11
- (C) Decomposition of N2O in presence of catalyst
- (D) Decomposition of N2O5
- (A) t^-1
- (B) mol dm³ t^-1
- (C) mol dm^-3 t^-1
- (D) mol dm^-3 t
- (A) k
- (B) -k
- (C) -k/2.303
- (D) k/2.303
- (A) 0
- (B) 2
- (C) 1.5
- (D) 1
- (A) 2
- (B) 1
- (C) 3
- (D) 4
49. A first order reaction has rate constant 1 x 10^-2 s^-1. What time will it take for 20 g of reactant to reduce to 5 g?
- (A) 138.6 s
- (B) 238.6 s
- (C) 693.0 s
- (D) 346.5 s
- (A) 1.07 x 10^-2 min^-1
- (B) 1.48 x 10^-2 min^-1
- (C) 1.84 x 10^-2 min^-1
- (D) 1.38 x 10^-2 min^-1
- (A)112.7 min
- (B) 56.35 min
- (C) 62.77 min
- (D) 98.7 min
- (A) 9.969 minutes
- (B) 4.12 minutes
- (C) 9.105 minutes
- (D) 12.05 minutes
- (A) 2.303/40 x log1/4
- (B) (2.303 x log 1.33)/40
- (C) (2.303 x log 4)/120
- (D) 2.303 x log 4/3
- (A) 144.3 min^-1
- (B) 6.93 min^-1
- (C) 69.3 min^-1
- (D) 6.93 x 10^-3 min^-1
- (A) 30 min
- (B) 60 min
- (C) 120 min
- (D) 40 min
O3(g) + O(g) → 2O2(g)
- (A) 3 and 1
- (B) 3 and 2
- (C) 4 and 2
- (D) 2 and 2
- (A) 4 x 10^-2 s^-1
- (B) 0.4 x 10^-2 s^-1
- (C) 2 x 10^-2 s^-1
- (D) 2.5 x 10^-5 s^-1
If rate constant is 1.62 Ms^-1 and concentration of NOBr is 2.00 x 10^-3M, what is the rate of reaction?
- (A) 2.46 x 10^-6 Ms^-1
- (B) 5.24 x 10^-6 Ms^-1
- (C) 6.48 x 10^-6 Ms^-1
- (D) 4.05 x 10^-5 Ms^-1
- (A) 1.0 x 10^-4 M/s
- (B) 4.0 x 10-4 M/s
- (C) 2.0 x 10^-4
- (D) 6.0 x 10^-4 M/s
- (A) 2N2O5(g) → 4NO2(g) + O2(g)
- (B) CH2 --CH2-- CH2 → CH3 -- CH= CH2
- (C) H2O2(l) → 2H2)(l) + O2(g)
- (D) CH3COOCH3(aq.) + H2O → CH3COOH(aq.) + CH3OH(aq.)
- (A) 4.0 m/s
- (B) 0.05 M/s
- (C) 0.0025 M/s
- (D) 1.0 M/s
- (A) rate = k[A]
- (B) rate = k[B2]
- (C) rate = k[A][B2]
- (D) rate = K[A]2[B2]
- (A) 2^( a – b)
- (B) a - b
- (C) a + b
- (D) 1/2^(a+b)
(i) NO2Cl(g) → 2NO2(g) + Cl2(g)
(ii) NO2Cl(g) + Cl(g) → NO2(g) + Cl2(g)
Identify the reaction intermediate.
- (A) NO2(g)
- (B) NO2Cl(g)
- (C) Cl(g)
- (D) C12(g)
65.1n
the reaction 2SO2(g) + O2(g) → 2SO3(g), the rate of disappearance of
SO2 is 1.28 x 10^-5 M/s. What is the rate of appearance of SO3?
- (A) 2.56 x 10^-5 M/s
- (B) 1.25 x 10^-5 M/s
- (C) 0.64 x 10^-5 M/s
- (D) 0.32 x 10^-5 M/s
66. A first order reaction takes 40 minutes for 30% decomposition. What is the half-life of reaction?
- (A) 59.5 min
- (B) 77.8 min
- (C) 67.8 min
- (D) 82.2 min
- (A) 65%
- (B) 25%
- (C) 75%
- (D) 60%
- (A) 8.6 x 10^-4 M/s
- (B) 5.2 x 10^-4 M/s
- (C) 2.6 x 10^-4 M/s
- (D) 7.8 x 10-4 M/s
- (A) mol^-1 dm³ s^-1
- (B) s^-1
- (C) mol dm^-3 s^-1
- (D) mol dm^-3 s
Calculate rate constant of reaction if concentration of N2O2 is 0.05 M and rate of reaction is
1.5 x 10^-6 mol L^-1 s^-1
- (A) 2.5 x 10^-5 s^-1
- (B) 3.0 x 10^-5 s^-1
- (C) 1.5 x 10^-5 s^-1
- (D) 2.0 x 10^-5 s^-1
- (A) 0.50 M
- (B) 0.125 M
- (C) 0.375 M
- (D) 0.060 M
- (A) Rate = k[A] [B]
- (B) Rate = k[A]² [B]^1/2
- (C) Rate = k[A]² [B]
- (D) Rate = k[A] [B]²
- (A) 7.215 x 10^-1 min^-1
- (B) 3.465 x 10^-2 min^-1
- (C) 1.386 x 10^-2 min^-1
- (D) 1.386 x 10^-1 min^-1
- (A) 77.7 min
- (B) 23.1 min
- (C) 42.7 min
- (D) 57.8 min
- (A) 0.125 M
- (B) 0.5 M
- (C) 1.25 M
- (D) 1.0 M
- (A) - 2.5 x 10^-3 s^-1
- (B) 2.5 x 10^-3 s^-1
- (C) 1.086 x 10^-3 s^-1
- (D) 5.757 x 10^-3 s^-1
77(78). A first order reaction, A → B takes 100 minutes for it's 90% completion. What is the rate constant of reaction?
- (A) 0.0460 min^-1
- (B) 0.0230 min^-1
- (D) 0.2303 min^-1
- (D) 0.4606 min^-1
- (A) 3364 sec
- (B) 360.0 sec
- (C) 560.0 sec
- (D) 5600 sec
- (A) 1.3 x 10^-5 s^-1
- (B) 2.1 x 10^-5 s^-1
- (C) 1.2 x 10^-5 s^-1
- (D) 1.6 x 10^-5 s^-1
- (A) -k
- (B) -kt
- (C) k
- (D) [A]0
81. A first order reaction is 50 % completed in 16 minutes. The percentage of reactant that will react in 32 minutes is
- (A) 75 %
- (B) 12-5%
- (C) 25%
- (D) 100%
82. Consider
the reaction; 2N2O5(g) → 4NO2(g) + O2(g). What is the rate of reaction,
when the concentration of NO2 increases to 5.2 x 10^-3 M in 100 sec?
- (A) 2 x 10^-5 M/s
- (B) 7.6 x 10^-4 M/s
- (C) 5 x 10^-4 M/s
- (D) 1.3 x 10^-5 M/s
- (A) -d[A]/2dt
- (B) -d[B]/dt
- (C) d[D]/dt
- (D) -d[C]/3dt
- (A) 4.158 x 10^-2 min^-1
- (B) 2.651 x 10^-2 min^-1
- (C) 1.155 x 10^-2 min^-1
- (D) 1.551 x 10^-2 min^-1
- (A) 414 sec
- (B) 444 sec
- (C) 424 sec
- (D) 434 sec
- (A) e - Ea/RT decreases
- (B) Ea/RT increases
- (C) -Ea/RT decreases
- (D) k decreases