Reaction Mechanism and Rate-Determining Step
Explore how the sequence of elementary steps (mechanism) relates to the observed rate law and the concept of the rate-determining step.
Why this shows up in the exam
JEE especially tests your ability to connect mechanisms to rate laws and identify the slowest step in a reaction.
How NEET tests this
Practise it
These are real questions from past NEET papers that test this exact idea.
Mechanism of a hypothetical reaction, X2+Y2 → 2XY, is given below : (i) X₂→ X + X (fast) (ii) X + Y₂XY + Y (slow) (iii) X + Y → XY (fast) The overall order of the reaction will be
Push further
More challenging9 harder questions built from the past papers above — a step up in difficulty, with distractors designed so you can't get there by elimination. Written and checked by our reviewers, not from a real paper.
Consider the catalytic decomposition of a gas 'A' on a solid surface. If the rate law is given by Rate = k[A] / (1 + K[A]), where k and K are constants. What would be the order of the reaction at very high concentrations of A?
More from Chemical Kinetics
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Arrhenius Equation and Activation Energy
Understand the Arrhenius equation, how temperature affects rate constants, and how to calculate and interpret activation energy graphically and mathematically.
Rate Law and Order of Reaction
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Rate of Reaction and Stoichiometry
Learn how the rate of a chemical reaction is defined, measured, and related to the stoichiometric coefficients of reactants and products.
Zero Order Reactions
Study the characteristics, integrated rate law, and half-life of zero order reactions, including graphical and mathematical aspects.
Energy Profile Diagrams and Reaction Energetics
Interpret potential energy diagrams for exothermic and endothermic reactions, and relate activation energy to enthalpy changes.