Bihar Board Class 12 (Science) Chemical Kinetics — practice questions
80 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice Bihar Board Class 12 (Science) Chemical Kinetics in the app →For a first-order reaction, the half-life period $t_{1/2}$ is related to the rate constant $k$ as:The units of the rate constant for a zero-order reaction are:A catalyst on the bench changes:For rate = k[A][B]², the overall order is:A first-order reaction plots linearly as:Half-life of a first-order reaction is:Per Arrhenius, raising T:For a reaction to proceed, colliding molecules must have:A catalyst:The RATE CONSTANT ($k$) of a reaction isFor a FIRST-ORDER reaction with rate constant $k$, the half-life is given byFor a ZERO-ORDER reaction $A \to \text{products}$, which graph is a STRAIGHT LINE?A first-order reaction has a rate constant of $k = 6.93\times 10^{-3}\,\text{s}^{-1}$ at a certain temperatureWhat is the overall order of a reaction with rate = k[A]^(3/2)[B]^(-1)?A reaction is second order in X. If [X] is tripled, the rate becomes how many times larger?For a first order reaction, 99.9% completion takes about how many half-lives?If the rate constant roughly doubles per 10 degree rise, a 30 degree rise raises it about how much?A first order reaction has t1/2 = 20 min. How long does 75% completion take?A zero order reaction starts at 0.8 mol/L with k = 0.02 mol L^-1 s^-1. When is the reactant used up?For 2NO + O2 giving 2NO2, rate = k[NO]^2[O2]. Doubling [NO] alone changes the rate how?Zero order half-life varies with initial concentration how?For a first order reaction, ln[R] plotted against time gives a line with what slope?Decomposition of ammonia on hot platinum at high pressure follows which order?Thermal decomposition of HI on a gold surface is a reaction of which order?Radioactive decay of unstable nuclei follows which kinetics?Hydrolysis of ethyl acetate in a large excess of water behaves as which type of reaction?Inversion of cane sugar in water is commonly classed as what?Which value can the molecularity of a reaction never take?Molecularity has meaning only for which kind of reaction?Decomposition of ammonium nitrite into N2 and water is what molecularity?The elementary step 2HI giving H2 + I2 has what molecularity?Why are reactions of molecularity three rare and slow?Which step controls the overall rate of a multi-step reaction?In the iodide-catalysed decomposition of H2O2, which species is the intermediate?A plot of ln k against 1/T is a straight line with what slope?What effect does a catalyst have on the equilibrium constant of a reaction?A substance added to a reaction that reduces its rate is called what?Which theory explains catalysis by a temporary catalyst-reactant bond?Collision theory of reaction rates was developed by whom?In collision theory, the steric factor P accounts for what?Threshold energy of a reaction equals which sum?Diamond should turn into graphite. Why is no change seen?For gaseous reactions with partial pressures, the rate has which units?How is instantaneous rate read from a concentration curve?On heating, how does the Maxwell-Boltzmann energy curve change?The equation first proposed by J.H. van't Hoff for temperature dependence was justified by whom?How must the rate law of a reaction be established?Mixing silver nitrate and sodium chloride solutions gives AgCl how fast?For a complex reaction, the overall order is decided by which step?A rate doubles from 298 K to 308 K. Its activation energy is aboutAs a reaction proceeds and reactants are used up, its rate usually does what?Raising temperature or lowering Ea affects the rate constant how?Which branch of chemistry tells how fast a reaction proceeds rather than only whether it is feasible?The expression relating reaction rate to reactant concentrations raised to powers is called theIn a rate law, the exponents of the concentration terms areFor 2NO + O2 giving 2NO2, the rate is k[NO]^2[O2]. What is the overall order?A reaction has rate = k[A]^(3/2)[B]^(-1). What is the overall order?Which statement about the order of a reaction is correct?A zero order reaction is one whose rateA rate constant of 3 x 10^-4 s^-1 indicates which order?A rate constant given as 2.3 x 10^-5 L mol^-1 s^-1 belongs to which order?If the concentration of X is tripled in a reaction second order in X, the rate becomesFor rate = k[A][B]^2, doubling only [B] changes the rate by what factor?A rate law is r = k[A]^(1/2)[B]^2. The order of the reaction isReactions that occur in a single step are calledThe number of species that must collide simultaneously in an elementary step is itsIn a multistep mechanism, the step that controls the overall rate is theWhich property can never be zero or a fraction?A plot of concentration [R] against time for a zero order reaction is a straight line with slopeA first order reaction has t1/2 of 6 min. Time for 99.9 percent completion is nearlyThe Arrhenius equation describes how the rate constant varies withThe energy difference between the activated complex and the reactants is theA rule of thumb says the rate of many reactions doubles for each rise of how much in temperature?A substance that decreases the rate of a reaction is calledCollision theory was developed in 1916 to 1918 byThe number of collisions per second per unit volume of a reaction mixture is calledWho studied the inversion of sucrose in 1850, pioneering chemical kinetics?Who received the first Nobel Prize in Chemistry in 1901 for laws of chemical dynamics?Crushing a solid reactant speeds a reaction because itWhich technique studies fast reactions by a sudden temperature or pressure change?