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Rate of reaction, rate law, order and molecularity

54 questions on Rate of reaction, rate law, order and molecularity from the Chemical Kinetics chapter: 10 NEET level, 22 JEE Main, 22 JEE Advanced. Each one opens with its answer and solution.

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The unit of the rate constant of a second order reaction, with concentration in mol L^-1 and time in seconds, is NEET level
For the elementary reaction 2A + B -> products, the rate law and the molecularity are NEET level
Which statement about molecularity is correct? NEET level
A reaction has the rate law rate = k[A]^1/2[B]^3/2. The overall order of the reaction is NEET level
For a reaction with rate law rate = k[A]^2[B], the concentration of A is tripled and that of B is halved. The rate changes by a factor of NEET level
The initial rates for A + B -> C at a fixed temperature are: (1) [A] = 0.10, [B] = 0.10 M, rate =2.0x10^-3 M s^-1; (2) [A] = 0.20, [B] = 0.10 M, rate =8.0x10^-3... JEE Main level
A reaction of order 3/2 is studied with concentration in mol L^-1 and time in minutes. The unit of its rate constant is JEE Main level
For 2N2O5 -> 4NO2 + O2, NO2 is formed at 5.6x10^-3 M s^-1. The rate of disappearance of N2O5 is JEE Main level
For A + B -> products the proposed mechanism is: step 1, A + B <=> C (fast, equilibrium); step 2, C + A -> products (slow). The rate law consistent with this me... JEE Main level
A gaseous reaction has the rate law rate = k[A][B]^2. The volume of the reaction vessel is reduced to one-third of its original value at constant temperature, w... JEE Main level
For a reaction with rate law rate = k[A]^2[B], the initial rate is 5.40x10^-4 M s^-1 when [A] = 0.30 M and [B] = 0.20 M. Calculate the initial rate, in units of... JEE Main level
The rate law of a reaction is rate = k[A]^n. When [A] is raised from 0.20 to 0.80 M the initial rate rises from 1.6x10^-3 to 1.28x10^-2 M s^-1. Find k in units ... JEE Main level
The rate constant of a second order reaction is 2.7x10^-3 L mol^-1 s^-1. Express it in 10^-3 m^3 mol^-1 h^-1 (use 1 L = 10^-3 m^3; two decimals). JEE Main level
Which of the following statements are correct? JEE Main level
For the concentration unit mol L^-1 and time in seconds, which of the following pairs of reaction order and unit of k are correct? JEE Main level
For A + B -> P the initial rates at fixed temperature are: [A] = 0.10, [B] = 0.20 M, rate =1.0x10^-3; [A] = 0.30, [B] = 0.20 M, rate =3.0x10^-3; [A] = 0.10, [B]... JEE Main level
Four initial-rate experiments for A + B + C -> P gave: ([A], [B], [C] in M; rate in M s^-1) (1) 0.10, 0.10, 0.20, 1.50x10^-3; (2) 0.20, 0.10, 0.20, 3.00x10^-3; ... JEE Advanced level
For 3A -> B the rate of the reaction is defined as r = -(1)/(3)(d[A])/(dt) and the rate law is r = k[A]^2. At [A] = 0.2 M, A disappears at 2.40x10^-3 M s^-1. Th... JEE Advanced level
A gas-phase reaction obeys -(dc_A)/(dt) = k_c c_A^2 with k_c = 0.5 L mol^-1 s^-1 at 300 K. Treat the gas as ideal (R = 0.0821 L atm mol^-1 K^-1). If the same ra... JEE Advanced level
For a reaction with rate = k[A]^n the initial rate is 6.4x10^-3 M s^-1 at [A] = 0.50 M and 8.0x10^-4 M s^-1 at [A] = 0.125 M. The initial rate at [A] = 0.0625 M... JEE Advanced level
For 2A + B -> P the initial rate of disappearance of A, -d[A]/dt, was measured: [A]=0.10, [B]=0.10 M: 2.60x10^-4; [A]=0.20, [B]=0.10 M: 1.04x10^-3; [A]=0.10, [B... JEE Advanced level
A gaseous second order reaction obeys -dp_A/dt = k_p p_A^2 with k_p = 2.0x10^-3 atm^-1 s^-1 at 400 K. Taking the gas as ideal, with R = 0.0821 L atm mol^-1 K^-1... JEE Advanced level
Mechanism: step 1, A + B <=> C, fast, with forward rate constant k_f = 1.2 L mol^-1 s^-1 and reverse rate constant k_r = 0.3 s^-1; step 2, C + A -> P, slow, wit... JEE Advanced level
For the overall reaction NO2 + CO -> NO + CO2 the proposed mechanism is: step 1, 2NO2 -> NO3 + NO (slow); step 2, NO3 + CO -> NO2 + CO2 (fast). Select the corre... JEE Advanced level
For a reaction in solution, consider the statements about rate. Select all correct ones. JEE Advanced level
For A + B -> P the initial rates are: [A]=0.10, [B]=0.04 M, rate =0.0160; [A]=0.20, [B]=0.04 M, rate =0.0320; [A]=0.10, [B]=0.16 M, rate =0.0320 M s^-1. Select ... JEE Advanced level
The rate constant of a reaction is k = 3.0x10^-4 mol L^-1 s^-1 at a given temperature. Select the correct statements. JEE Advanced level
In the mechanism A <=>[k_1][k_-1] I, I ->[k_2] P with k_1 = 2.0x10^-3 s^-1, k_-1 = 3.0x10^-2 s^-1, k_2 = 1.0x10^-2 s^-1, the steady-state approximation for I (u... JEE Advanced level
For the reaction 2N2O5 -> 4NO2 + O2, which set of equalities correctly gives the rate of reaction? NEET level
Mechanism for NO2 + CO -> NO + CO2: slow 2NO2 -> NO3 + NO with step rate = k[NO2]^2, k = 0.50 M^-1 s^-1; fast NO3 + CO -> NO2 + CO2. At [NO2] = 0.20 M and [CO] ... JEE Advanced level
Acid-catalysed conversion: S + H+ <=> SH+ (fast, constant K), then SH+ + H2O -> P + H+ (slow, solvent in large excess). Experiment 1 uses [S] = 0.10 M, [H+] = 0... JEE Advanced level
A mechanism for A + 2B -> D is: step 1 (slow) A + B -> C; step 2 (fast) C + B -> D, where C is an intermediate. The rate law is JEE Main level
In the Haber reaction N2 + 3H2 -> 2NH3, ammonia forms at a rate of 0.60 mol L^-1 min^-1. At what rate (in mol L^-1 min^-1) is hydrogen consumed? NEET level
The decomposition 2H2O2 -> 2H2O + O2 of 50.0 mL of solution gives 33.6 mL of O2 (at STP, molar volume 22.4 L mol^-1) in the first 10.0 min. Taking the volume as... JEE Main level
For 3A -> 2B, B is formed at 0.060 M s^-1. The rate of disappearance of A, in M s^-1, is JEE Main level
For the scheme A -> I (k_1 = 0.060 s^-1), I -> A (k_-1 = 0.50 s^-1), I -> P (k_2 = 0.25 s^-1), all first order, apply the steady-state approximation to I. When ... JEE Advanced level
For A -> products, the concentration of A falls from 0.80 M to 0.50 M in 30 s. The average rate of reaction over this interval, in M s^-1, is NEET level
For 2A -> P, the measured concentrations of A are 1.000 M at 0 s, 0.670 M at 20 s and 0.301 M at 60 s. The best estimate of the rate of reaction (IUPAC, per uni... JEE Advanced level
Ozone decomposition 2O3 -> 3O2 proceeds by: fast equilibrium O3 <=> O2 + O (constant K), then slow O + O3 -> 2O2 (constant k_2). Select the correct statement(s)... JEE Advanced level
In 4NH3 + 5O2 -> 4NO + 6H2O, ammonia is consumed at 0.24 M s^-1. The rate of formation of water, in M s^-1, is JEE Main level
For 2NO + O2 -> 2NO2 the mechanism is: fast equilibrium 2NO <=> N2O2 (constant K), then slow N2O2 + O2 -> 2NO2 (constant k_2). The rate expressed in terms of re... JEE Main level
For A -> products the concentration of A at t = 0, 20, 40, 60 s is 1.00, 0.72, 0.52, 0.37 M respectively. The average rate of disappearance of A between 20 s an... JEE Main level
A mechanism for 2A + B -> products is: fast equilibrium A + B <=> I (constant K), then slow I + A -> products (constant k_2). Select the correct statement(s). JEE Advanced level
In 2N2O5 -> 4NO2 + O2 (molar masses: NO2 = 46, N2O5 = 108 g mol^-1), NO2 is formed at 2.76 g L^-1 s^-1. What mass of N2O5 (in g) is consumed per litre per minut... JEE Advanced level
In A <=>[k_1][k_-1] I ->[k_2] P with k_1 = 0.010 s^-1, k_-1 = 0.002 s^-1, k_2 = 0.200 s^-1, use the steady-state approximation for I. Select the correct stateme... JEE Advanced level
An ideal gas A decomposes in a rigid vessel at 350 K with -d[A]/dt = 3.0x10^-3 M s^-1. Using R = 0.0821 L atm mol^-1 K^-1, find -dp_A/dt in units of 10^-2 atm s... JEE Main level
In a multi-step mechanism, the rate-determining step is NEET level
On a plot of concentration of a reactant against time, the instantaneous rate at time t is obtained from NEET level
For A -> products, the concentration of A at t = 0, 10, 20, 30 s is 0.800, 0.640, 0.512, 0.4096 M (a smooth, convex decay). Select the correct statement(s). JEE Advanced level
Which of the following statements about reaction mechanisms are correct? JEE Main level
For 2A -> 3B, the concentration of A changes from 0.600 M to 0.420 M in 75 s. Taking the rate of reaction as -(1)/(2)Delta[A]/Delta t, find its value in units o... JEE Main level
The equation A -> P is rewritten as 2A -> 2P for the same reaction. Using the IUPAC definition of rate of reaction ((1)/(nu_i)(d[i])/(dt)), which is correct? JEE Main level
Pure PH3 decomposes in a rigid vessel at constant temperature: 4PH3(g) -> P4(g) + 6H2(g) (all species gaseous, ideal). Initially the total pressure rises at 18.... JEE Advanced level
For the reaction 2A + B -> 3C + D, A is consumed at 0.30 M s^-1 at a certain instant. Select the correct statement(s). JEE Main level