ISC Class 12 Chemical Kinetics — practice questions
40 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice ISC Class 12 Chemical Kinetics in the app →For the reaction R -> P, the concentration of R changes from 0.03 M to 0.02 M in 25 minutes. What is the averaIn the reaction 2A -> Products, the concentration of A decreases from 0.5 mol L^-1 to 0.4 mol L^-1 in 10 minutFor the reaction 2N2O5(g) -> 4NO2(g) + O2(g), if the rate of reaction is r, what is the rate of formation of NThe decomposition of N2O5 in CCl4 follows 2N2O5 -> 4NO2 + O2. Its concentration falls from 2.33 mol L^-1 to 2.Which statement best defines the rate law (rate expression) of a chemical reaction?For the reaction 2NO(g) + O2(g) -> 2NO2(g), doubling [NO] at constant [O2] quadruples the rate, and doubling [A reaction has the rate expression Rate = k[A]^1/2 [B]^3/2. What is the overall order of the reaction?A reaction has the rate expression Rate = k[A]^3/2 [B]^-1. What is the overall order of the reaction?For the reaction A + B -> Product, the rate law is r = k[A]^1/2 [B]^2. What is the order of the reaction?A rate constant is found to have units L mol^-1 s^-1. What is the order of the reaction?What are the SI units of the rate constant for a first order reaction?What are the SI units of the rate constant for a zero order reaction?Which of the following statements about order and molecularity is correct?The decomposition of H2O2 catalysed by I^- has rate = k[H2O2][I^-] and proceeds via a slow first step. What isFor the conversion of X to Y following second order kinetics with rate = k[X]^2, if [X] is increased to three A reaction is second order with respect to a reactant. If the concentration of that reactant is reduced to halWhich expression correctly gives the integrated rate law for a zero order reaction R -> P?For a zero order reaction, a plot of [R] against time t gives a straight line. What does the slope of this linThe decomposition of NH3 on a hot platinum surface is zero order with k = 2.5 x 10^-4 mol L^-1 s^-1 for the reWhich equation correctly expresses the rate constant of a first order reaction in terms of initial concentratiFor the first order reaction N2O5 -> 2NO2 + 1/2 O2 at 318 K, [N2O5] falls from 1.24 x 10^-2 to 0.20 x 10^-2 moIn the first order gas phase reaction A(g) -> B(g) + C(g) followed by total pressure, pi is the initial pressuWhich statement about the half-life of reactions is correct?A first order reaction has a rate constant k = 5.5 x 10^-14 s^-1. What is its half-life?For a zero order reaction with initial concentration [R]0 = 0.50 mol L^-1 and rate constant k = 1.0 x 10^-2 moFor a first order reaction, show that the time required for 99.9% completion is how many times the half-life tA first order reaction takes 40 min for 30% decomposition. What is its half-life? (log(10/7) = 0.155)The rate constant for a first order reaction is 60 s^-1. Approximately how much time is required to reduce theFor a certain reaction A -> Products with k = 2.0 x 10^-2 s^-1, the initial concentration of A is 1.0 mol L^-1Sucrose decomposes by first order kinetics with t1/2 = 3.00 hours. What fraction of the sucrose sample remainsWhat is the central idea of the Arrhenius equation k = A e^(-Ea/RT)?In the Arrhenius plot of ln k versus 1/T, what does the slope of the straight line equal?The rate constants of a reaction at 500 K and 700 K are 0.02 s^-1 and 0.07 s^-1 respectively. What is the actiThe first order rate constant for decomposition of ethyl iodide is 1.60 x 10^-5 s^-1 at 600 K with Ea = 209 kJHow does a catalyst increase the rate of a chemical reaction?According to collision theory, in the modified rate expression Rate = P Z_AB e^(-Ea/RT), what does the steric In collision theory, what is meant by the collision frequency (Z)?In a pseudo first order reaction, [A]/mol L^-1 reads 0.31 at t = 30 s and 0.17 at t = 60 s. What is the averagThe half-life for the radioactive decay of carbon-14 is 5730 years and decay is first order. An artifact contaIt is observed that for many reactions the rate constant nearly doubles for a rise in temperature of how much?