First Order Reactions
Master the integrated rate law, half-life, percent completion, and graphical analysis for first order reactions.
Why this shows up in the exam
First order kinetics are frequently tested for calculations, conceptual understanding, and graphical interpretation.
How NEET tests this
Practise it
These are real questions from past NEET papers that test this exact idea.
For a first order reaction A → B the reaction rate at reactant concentration of 0.01 M is found to be 2.0 x 10⁻⁵ mol L⁻¹ s⁻¹. The half-life period of the reaction is
Push further
More challenging26 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.
The decomposition of hydrogen peroxide (H₂O₂) is a first-order reaction. If 75% of a sample of H₂O₂ decomposes in 40 minutes, what is the time required for 50% decomposition?
More from Chemical Kinetics
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
Understand how to write the rate law, determine the order of a reaction, and interpret the effect of concentration changes on reaction rate.
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.
Catalysis and Enzymes
Examine how catalysts, including enzymes, affect reaction rates and activation energy, and their role in biochemical reactions.