reaksi

Reaksi is a term meaning reaction. In Indonesian and Malay usage, it broadly refers to a process that transforms matter or a response to stimuli. In science, the word is used for chemical reactions, as well as biological, physical, and social responses.

In chemistry, a chemical reaction is a process in which one or more reactants are transformed into products, with bonds broken and formed and energy exchanged with the surroundings. Reactions are described by balanced chemical equations that reflect conserved atoms and stoichiometry. The rate of a reaction depends on factors such as temperature, concentration, surface area, pressure, and the presence of catalysts. Activation energy is the minimum energy required for the reaction to proceed, and catalysts work by lowering this barrier. Reactions can be exothermic or endothermic, and many reach a dynamic state called equilibrium where the forward and reverse rates are equal.

Common types include synthesis, decomposition, single-displacement, double-displacement, combustion, and redox reactions. Examples are the synthesis of water from hydrogen and oxygen, the combustion of methane, and the rusting of iron.

Observations of reactions often include a color change, formation of a precipitate, evolution of a gas, odor changes, and temperature change.

Beyond chemistry, the term denotes responses to events or stimuli in other fields. A person’s reaction to news, or a biological reaction such as a metabolic or signaling pathway, are common usages.