"A reaction mechanism is the step by step sequence of elementary reactions by which overall chemical reaction occurs."
The series of steps that a reaction goes through to form products.
Elementary Reactions: The simplest type of chemical reactions that occur in a single step and involve the breaking and forming of bonds.
Rate Laws: Mathematical expressions used to describe the rate at which a reaction occurs as a function of different variables such as concentration, temperature, and pressure.
Reaction Intermediates: Species that are formed and consumed during a chemical reaction but are not present in the reactants or products.
Reaction Kinetics: The study of how a chemical reaction progresses over time, including the rates at which different processes occur.
Transition States: High-energy intermediates that exist between the reactants and products in a chemical reaction.
Activation Energy: The minimum amount of energy required to initiate a chemical reaction, often referred to as the energy barrier.
Reaction Mechanisms: The series of steps that describe how a chemical reaction occurs, including the intermediates, transition states, and elementary reactions involved.
Homogeneous Catalysis: A type of catalysis in which the catalyst is present in the same phase as the reactants, often by forming intermediate complexes.
Heterogeneous Catalysis: A type of catalysis where the catalyst exists in a different phase than the reactants, often by adsorbing the reactants onto the catalyst surface.
Enzyme Catalysis: The process by which enzymes, specialized biological molecules, speed up chemical reactions in living organisms.
Michaelis-Menten Kinetics: A model used to describe the behavior of enzymes when the substrate concentration is low, and enzyme-substrate complexes are rapidly formed and broken down.
Multi-Step Reactions: Chemical reactions that involve more than one elementary step, often with different rates and intermediates.
Chain Reactions: Reactions that involve the formation and consumption of reactive intermediates or radicals, leading to multiple reactions in a cycle.
Collision Theory: The theory that chemical reactions occur when molecules collide with the right orientation and sufficient energy to overcome the activation energy barrier.
Reaction Dynamics: The investigation of how the energy and momentum of reacting molecules, atoms, and ions affect the outcome of a chemical reaction.
Elementary reactions: These are simple reactions that happen in a single step without the interference of any intermediate species.
Chain reactions: They are a series of reactions that take place in a chain of reactive species, leading to explosive polymerization or combustion.
Radical reactions: Radical reactions involve reactive intermediates called free radicals in a chain mechanism that lead to products with double or triple bonds.
Acid-base reactions: The transfer of protons (H+) from an acid to a base or an electron-pair (Lewis) donated to the Acid causes the reaction at a profound level.
Substitution reactions: A substitution reaction is one in which an atom or group is replaced by another atom or group in a molecule, taking place either in a single step or by two steps.
Addition reactions: Addition reactions are reactions in which one or more atoms or groups are added to an unsaturated compound to form a more complex compound like the polymerization of ethene.
Elimination reactions: Elimination reaction is one in which a single molecule will split into two or more smaller molecules by the loss of some atoms.
Photochemical reactions: Photochemical reactions triggered by photons of light are a type of mechanism that occurs when the incoming photon induces a reaction or sustains the new state.
Rearrangement reactions: Rearrangement reactions are transformations in which the skeletal structure of the molecule is changed.
"A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of an overall chemical reaction."
"The detailed steps of a reaction are not observable in most cases."
"The conjectured mechanism is chosen because it is thermodynamically feasible and has experimental support in isolated intermediates (see next section) or other quantitative and qualitative characteristics of the reaction."
"A complete mechanism must also explain the reason for the reactants and catalyst used, the stereochemistry observed in reactants and products, all products formed and the amount of each."
"The electron or arrow pushing method is often used in illustrating a reaction mechanism; for example, see the illustration of the mechanism for benzoin condensation in the following examples section."
"Often what appears to be a single-step conversion is in fact a multistep reaction." Quotes: