chemical change

If you are waiting for some bananas to ripen, you are waiting for a chemical change. A chemical change occurs when a new substance is formed through a chemical reaction like when fruit ripens or rots.

When something undergoes a "chemical reaction" and a new substance is formed as a result, we call this chemical change. In some instances, simply applying heat can cause a chemical change. Cooking pancakes, for instance, is an example of a chemical change; the pancake batter "changes" from a liquid to a solid. Rust forming on metal is another example of a chemical change. The iron reacts with water and oxygen to create a new substance — rust.

Definitions of chemical change
  1. noun
    (chemistry) any process determined by the atomic and molecular composition and structure of the substances involved
    synonyms: chemical action, chemical process
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    types:
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    acylation
    the process of introducing an acyl group into a compound
    agglutinating activity, agglutination
    the coalescing of small particles that are suspended in solution; these larger masses are then (usually) precipitated
    amylolysis
    conversion of starch to sugar
    association
    (chemistry) any process of combination (especially in solution) that depends on relatively weak chemical bonding
    blueing, bluing
    a process that makes something blue (or bluish)
    calcification
    a process that impregnates something with calcium (or calcium salts)
    catalysis, contact action
    acceleration of a chemical reaction induced the presence of material that is chemically unchanged at the end of the reaction
    chelation
    the process of forming a ring by forming one or more hydrogen bonds
    chemical reaction, reaction
    (chemistry) a process in which one or more substances are changed into others
    chlorination
    the addition or substitution of chlorine in organic compounds
    cleavage
    the breaking of a chemical bond in a molecule resulting in smaller molecules
    corroding, corrosion, erosion
    erosion by chemical action
    cracking
    the process whereby heavy molecules of naphtha or petroleum are broken down into hydrocarbons of lower molecular weight (especially in the oil-refining process)
    deamination, deaminization
    removal of the amino radical from an amino acid or other amino compound
    decalcification
    loss of calcium from bones or teeth
    decarboxylation
    the process of removing a carboxyl group from a chemical compound (usually replacing it with hydrogen)
    de-iodination
    the removal of iodine atoms from organic compounds
    demineralisation, demineralization
    the removal of minerals and mineral salts from a liquid (especially from water)
    desalination, desalinisation, desalinization
    the removal of salt (especially from sea water)
    digestion
    the process of decomposing organic matter (as in sewage) by bacteria or by chemical action or heat
    dissociation
    (chemistry) the temporary or reversible process in which a molecule or ion is broken down into smaller molecules or ions
    gasification
    the process of changing into gas
    gassing
    the process of interacting with gas
    hydrogenation
    a chemical process that adds hydrogen atoms to an unsaturated oil
    intumescence, intumescency, swelling
    the increase in volume of certain substances when they are heated (often accompanied by release of water)
    inversion
    a chemical process in which the direction of optical rotation of a substance is reversed from dextrorotatory to levorotary or vice versa
    iodination
    the substitution or addition of iodine atoms in organic compounds
    chemical mechanism, mechanism
    the atomic process that occurs during a chemical reaction
    nitrification
    the chemical process in which a nitro group is added to an organic compound (or substituted for another group in an organic compound)
    peptisation, peptization
    the process of converting to a sol; bringing to a colloidal solution
    photosynthesis
    synthesis of compounds with the aid of radiant energy (especially in plants)
    polymerisation, polymerization
    a chemical process that combines several monomers to form a polymer or polymeric compound
    precipitation
    the process of forming a chemical precipitate
    proteolysis
    the hydrolysis of proteins into peptides and amino acids by cleavage of their peptide bonds
    pyrochemical process, pyrochemistry
    processes for chemical reactions at high temperatures
    sequestration
    the action of forming a chelate or other stable compound with an ion or atom or molecule so that it is no longer available for reactions
    synaeresis, syneresis
    the separation of liquid from a gel that is caused by contraction (as in cheese making)
    synthesis
    the process of producing a chemical compound (usually by the union of simpler chemical compounds)
    transamination
    the process of transfering an amino group from one compound to another
    transamination
    the process of transposing an amino group within a chemical compound
    ferment, fermentation, fermenting, zymolysis, zymosis
    a process in which an agent causes an organic substance to break down into simpler substances; especially, the anaerobic breakdown of sugar into alcohol
    acetylation
    the process of introducing an acetyl group into a compound
    addition reaction
    a chemical reaction in which one molecule is added to another
    aldol reaction
    a reaction of aldehydes resulting in an aldol
    autocatalysis
    catalysis in which the catalyst is one of the products of the reaction
    biochemical mechanism
    a chemical mechanism involved in vital processes occurring in living organisms
    biogenesis, biosynthesis
    production of a chemical compound by a living organism
    bottom fermentation
    a slow kind of alcoholic fermentation at a temperature low enough that the yeast cells can sink to the bottom of the fermenting liquid; used in the production of lager
    chain reaction
    a series of chemical reactions in which the product of one is a reactant in the next
    chemical equilibrium, equilibrium
    a chemical reaction and its reverse proceed at equal rates
    chemosynthesis
    synthesis of carbohydrate from carbon dioxide and water; limited to certain bacteria and fungi
    chemical decomposition reaction, decomposition, decomposition reaction
    (chemistry) separation of a substance into two or more substances that may differ from each other and from the original substance
    displacement, displacement reaction
    (chemistry) a reaction in which an elementary substance displaces and sets free a constituent element from a compound
    double decomposition, double decomposition reaction, metathesis
    a chemical reaction between two compounds in which parts of each are interchanged to form two new compounds (AB+CD=AD+CB)
    elimination reaction
    a chemical reaction in which a molecule decomposes to two different molecules
    endothermic reaction
    a chemical reaction accompanied by the absorption of heat
    exothermic reaction
    a chemical reaction accompanied by the evolution of heat
    hydration
    the process of combining with water; usually reversible
    hydrocracking
    the process whereby hydrocarbon molecules of petroleum are broken down into kerosene and gasolene by the addition of hydrogen under high pressure in the presence of a catalyst
    hydrolysis
    a chemical reaction in which water reacts with a compound to produce other compounds; involves the splitting of a bond and the addition of the hydrogen cation and the hydroxide anion from the water
    neutralisation, neutralisation reaction, neutralization, neutralization reaction
    a chemical reaction in which an acid and a base interact with the formation of a salt; with strong acids and bases the essential reaction is the combination of hydrogen ions with hydroxyl ions to form water
    nucleosynthesis
    (astronomy) the cosmic synthesis of atoms more complex than the hydrogen atom
    ossification
    the calcification of soft tissue into a bonelike material
    oxidation, oxidisation, oxidization
    the process of oxidizing; the addition of oxygen to a compound with a loss of electrons; always occurs accompanied by reduction
    oxidation-reduction, oxidoreduction, redox
    a reversible chemical reaction in which one reaction is an oxidation and the reverse is a reduction
    photochemical reaction
    a chemical reaction produced by the action of light
    indentation, pitting, roughness
    the formation of small pits in a surface as a consequence of corrosion
    prechlorination
    chlorination prior to another chemical process
    reducing, reduction
    any process in which electrons are added to an atom or ion (as by removing oxygen or adding hydrogen); always occurs accompanied by oxidation of the reducing agent
    rust, rusting
    the formation of reddish-brown ferric oxides on iron by low-temperature oxidation in the presence of water
    saponification
    a chemical reaction in which an ester is heated with an alkali (especially the alkaline hydrolysis of a fat or oil to make soap)
    solvation
    a chemical process in which solvent molecules and molecules or ions of the solute combine to form a compound
    top fermentation
    a violent kind of alcoholic fermentation at a temperature high enough to carry the yeast cells to the top of the fermenting liquid; used in the production of ale
    vinification
    the process whereby fermentation changes grape juice into wine
    type of:
    action, activity, natural action, natural process
    a process existing in or produced by nature (rather than by the intent of human beings)
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