All Words Glossary

Glossary of Chemistry Terms
beginning with letter R
Browse the Chemistry Glossary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 

R Tweet Definition of R Like Definition of R on Facebook
  1. The eighteenth letter of the Appendix:Roman script, English alphabet, preceded by Q and followed by S.
  1. (context, US politics) Republican
    1. (film certification) restricted
    2. reverse
    3. right (as opposed to left)
    4. (context, handbells) ring
    5. (context, baseball, cricket) The statistic reporting the number of runs scored by a player
    6. Thursday
racemate Tweet Definition of racemate Like Definition of racemate on Facebook
  1. (chemistry) a racemic mixture
  2. (chemistry) any salt or ester of racemic acid
racemic Tweet Definition of racemic Like Definition of racemic on Facebook
  1. (chemistry) containing equal amounts of dextrorotatory and levorotatory stereoisomers and therefore not being optically active; typically, will be synthetic rather than natural
racemic acid Tweet Definition of racemic acid Like Definition of racemic acid on Facebook
  1. (chemistry) an equal mixture of the d- and l- forms of tartaric acid found in grape juice; the isomers can be separated via crystallization
racemization Tweet Definition of racemization Like Definition of racemization on Facebook
  1. (chemistry) the formation of a racemate from a pure enantiomer
radiocarbon Tweet Definition of radiocarbon Like Definition of radiocarbon on Facebook
  1. A radioactive isotope of carbon, especially (nuclide, 14, 6, C)
radiochemistry Tweet Definition of radiochemistry Like Definition of radiochemistry on Facebook
  1. (chemistry) the chemistry of radioactive substances
  2. (chemistry) the use of radioisotopes to study the kinetics of chemical reactions
radiostrontium Tweet Definition of radiostrontium Like Definition of radiostrontium on Facebook
  1. any radioactive isotope of strontium, especially (nuclide, 90, 38, Sr)
radium Tweet Definition of radium Like Definition of radium on Facebook
  1. a radioactive metallic chemical element (symbol Ra) with an atomic number of 88.
radon Tweet Definition of radon Like Definition of radon on Facebook
  1. A radioactive chemical element (symbol Rn, formerly Ro) with atomic number 86, one of the noble gases.
raffinate Tweet Definition of raffinate Like Definition of raffinate on Facebook
  1. (chemistry) a solution from which some material has been removed by extraction with an immiscible liquid
rape oil Tweet Definition of rape oil Like Definition of rape oil on Facebook
  1. a thick brownish-yellow oil expressed from rapeseed, used chiefly for lubricating and in the manufacture of soap and india-rubber
The number of seconds taken by the oil to flow up to the 50 c.c. mark on the flask is noted, and the results brought into comparison with the viscosity of rape oil, that being the oil with which the apparatus is standardised.--Vivian Byam Lewes Oil Fuel (1913) vi. 177
Rape-Oil is sweet, and on the contrary the Linseed bitter.--Pierre Pomet A Compleat History of Druggs (1712) I. 10
Rape oyle that is used in Lampes and therefore called Lampe Oyle.--John Parkinson, Theatrum botanicum: the theater of plants, or an herball of a large extent (1640) 861
rare earth Tweet Definition of rare earth Like Definition of rare earth on Facebook
  1. (chemistry) naturally occurring oxides of the lanthanide metals; they are widely distributed in relatively small concentrations and are used in glassmaking, ceramic glazes etc
react Tweet Definition of react Like Definition of react on Facebook
  1. To act or perform a second time; to do over again; as, to react a play; the same scenes were reacted at Rome.
  2. To return an impulse or impression; to resist the action of another body by an opposite force; as, every body reacts on the body that impels it from its natural state.
  3. To act upon each other; to exercise a reciprocal or a reverse effect, as two or more chemical agents; to act in opposition.
reactant Tweet Definition of reactant Like Definition of reactant on Facebook
  1. (chemistry) any of the participants present at the start of a chemical reaction
reaction Tweet Definition of reaction Like Definition of reaction on Facebook
  1. An action or statement in response to a stimulus or other event
The announcement of the verdict brought a violent .
You were in the coutroom. What is your ?
When I last tried to eat strawberries I had a terrible allergic .
  1. (chemistry) A transformation in which one or more substances is converted into another by combination or decomposition
    In this , the acid and base will neutralize each other, producing a salt.
reactivity Tweet Definition of reactivity Like Definition of reactivity on Facebook
  1. responsiveness to stimulation
  1. (chemistry) relative susceptability to chemical reaction
reactor Tweet Definition of reactor Like Definition of reactor on Facebook
  1. A person who behaves in response to a suggestion, stimulation or some other influence.
  2. A device which uses atomic energy to produce heat.
  3. A chemical substance which responds to the presence or contact with another substance.
reagent Tweet Definition of reagent Like Definition of reagent on Facebook
  1. (chemistry) A usually available or readily made compound or known mixture of compounds used to treat materials, samples, other compounds or reactants in a laboratory or sometimes an industrial setting.
receiver Tweet Definition of receiver Like Definition of receiver on Facebook
  1. A person who receives something.
  2. A person who acts as trustee for a bankrupt.
  3. A person who accepts stolen goods.
  4. (football) A person who accepts the ball after it has been snapped.
  5. Any of several electronic devices that receives signals and converts them into sound or vision
  6. A court administrator
rectify Tweet Definition of rectify Like Definition of rectify on Facebook
verb (rectif, i, ed)
  1. (transitive) To correct or amend something.
  2. (transitive, chemistry) To purify or refine, especially by distillation.
  3. (transitive, electronics) To convert alternating current into direct current.
  4. (transitive) To add water to alcoholic spirit to adjust its proof.
red fire Tweet Definition of red fire Like Definition of red fire on Facebook
  1. a chemical mixture used in fireworks and flare, flares that burns with a bright red flame.
red lead Tweet Definition of red lead Like Definition of red lead on Facebook
noun (-, sg=red lead)
  1. a bright red, poisonous oxide of lead, Pb3O4, used as a pigment and in glass and ceramics
redox Tweet Definition of redox Like Definition of redox on Facebook
  1. a reversible chemical reaction in which one reaction is an oxidation and the reverse is a reduction
reducing agent Tweet Definition of reducing agent Like Definition of reducing agent on Facebook
  1. (chemistry) any substance that reduces, or donates electrons to, another; in so doing, it becomes oxidized
reduction Tweet Definition of reduction Like Definition of reduction on Facebook
  1. The act, process, or result of reducing
  2. The amount by which something is reduced
    • A 5% in robberies
      1. (chemistry) A reaction in which electrons are gained and valence is reduced; often by the removal of oxygen or the addition of hydrogen
      2. (cooking) The process of rapidly boiling a sauce to concentrate it
reference electrode Tweet Definition of reference electrode Like Definition of reference electrode on Facebook
  1. (chemistry),(physics) an electrode with a stable and accurately known electrode potential
reform Tweet Definition of reform Like Definition of reform on Facebook
  1. Amendment of what is defective, vicious, corrupt, or depraved; reformation; as, reform of elections; reform of government.
  1. To put into a new and improved form or condition; to restore to a former good state, or bring from bad to good; to change from worse to better; to amend; to correct; as, to reform a profligate man; to reform corrupt manners or morals.
  2. To return to a good state; to amend or correct one's own character or habits; as, a person of settled habits of vice will seldom reform.
reforming Tweet Definition of reforming Like Definition of reforming on Facebook
  1. (chemistry) a catalytic process, whereby short-chain molecules are combined to make larger ones; used in the petrochemical industry
  1. (present participle of, reform)
residence Tweet Definition of residence Like Definition of residence on Facebook
  1. the place where one lives.
  2. the place where a corporation is established.
  3. a building used as a home.
residence time Tweet Definition of residence time Like Definition of residence time on Facebook
  1. (hydrology) The average time a particular molecule of water will remain in a body of water.
residuum Tweet Definition of residuum Like Definition of residuum on Facebook
noun (residu, a)
  1. The solid material remaining after the liquid in which it was dissolved has been evaporated; a residue.
resin Tweet Definition of resin Like Definition of resin on Facebook
  1. Any of various yellowish viscous liquids or soft solids of plant origin; used in lacquers, varnishes and many other applications; chemically they are mostly hydrocarbons, often polycyclic
  2. Any synthetic compound of similar properties
resinify Tweet Definition of resinify Like Definition of resinify on Facebook
verb (resinifies, resinifying, resinified, resinified)
  1. To make or become a resin
After putting the coated parts together, Jon waited for the chemical adhesive to resinify
  1. To become resin-like, resinous
Exposed to the elements, over time the oil had resinified
resinous Tweet Definition of resinous Like Definition of resinous on Facebook
  1. Of, or pertaining to, resin.
  2. Resin-like.
resist Tweet Definition of resist Like Definition of resist on Facebook
  1. a protective covering
  1. to attempt to counter the actions or effects of someone or something (transitive)
  2. to withstand such actions (transitive)
  3. to oppose (intransitive)
resonance Tweet Definition of resonance Like Definition of resonance on Facebook
  1. The condition of being resonant.
  2. Something that evokes an association, or a strong emotion.
  3. (physics) The increase in the amplitude of an oscillation of a system under the influence of a periodic force whose frequency is close to that of the system's natural frequency.
  4. (context, nuclear physics) A short-lived subatomic particle that cannot be observed directly.
    • 2004: When experiments with the first "atom-smashers" took place in the 1950s to 1960s, many short-lived heavier siblings of the proton and neutron, known as "resonances", were discovered. " Frank Close, Particle Physics: A Very Short Introduction (Oxford 2004, p. 35)
      1. An increase in the strength or duration of a musical tone produced by sympathetic vibration.
      2. (chemistry) The property of a compound that can be visualized as having two structures differing only in the distribution of electrons.
      (rfc, reword/combine definitions - should be three?)
retort Tweet Definition of retort Like Definition of retort on Facebook
  1. A sharp or witty reply, or one which turns an argument against its originator.
  2. (chemistry) A flask with a rounded base and a long neck that is bent down and taper, tapered, used to heat a liquid for distillation.
  • 1893, A large curved was boiling furiously in the bluish flame of a Bunsen burner, and the distilled drops were condensing into a two-litre measure. " Arthur Conan Doyle, "The Naval Treaty" (Norton 2005, p.670)
    1. A container in which material is subjected to high temperature, temperatures as part of an industrial manufacturing process, especially during the smelt, smelting and forge, forging of metal.
  1. To say something sharp or witty in answer to a remark or accusation.
  2. To make a remark which reverses an argument upon its originator.
  3. To heat in a retort.
reverse osmosis Tweet Definition of reverse osmosis Like Definition of reverse osmosis on Facebook
  1. (chemistry) a technique whereby a solution is forced through a semipermeable membrane under pressure; used to generate drinkable water from sea water, or to separate chemical compounds
revive Tweet Definition of revive Like Definition of revive on Facebook
verb (reviv, ing)
  1. To return to life; to recover life or strength; to live anew; to become reanimated or reinvigorated.
The Lord heard the voice of Elijah; and the soul of the child came into again, and he revived. 1 Kings xvii. 22.
  1. Hence, to recover from a state of oblivion, obscurity, neglect, or depression; as, classical learning revived in the fifteenth century.
  2. To recover its natural or metallic state, as a metal.
  3. To restore, or bring again to life; to reanimate.
  4. To raise from coma, languor, depression, or discouragement; to bring into action after a suspension.
  5. Hence, to recover from a state of neglect or disuse; as, to revive letters or learning.
  6. To renew in the mind or memory; to bring to recollection; to recall attention to; to reawaken.
  7. To restore or reduce to its natural or metallic state; as, to revive a metal after calcination.
rhodamine Tweet Definition of rhodamine Like Definition of rhodamine on Facebook
  1. (chemistry) any of a class of pink to red polycyclic fluorone dyes
rhodium Tweet Definition of rhodium Like Definition of rhodium on Facebook
  1. a metallic chemical element (symbol Rh) with an atomic number of 45.
ricin Tweet Definition of ricin Like Definition of ricin on Facebook
  1. (context, protein, poison) A toxic protein extracted from the castor bean.
ricinoleic acid Tweet Definition of ricinoleic acid Like Definition of ricinoleic acid on Facebook
  1. (fatty acid) An unsaturated fatty acid, 12-hydroxy-oleic acid, present in castor oil; used in textile finishing, ink and soap.
Ring Tweet Definition of Ring Like Definition of Ring on Facebook
proper noun (infl, en, proper noun)
  1. An Irish family name.
RN Tweet Definition of RN Like Definition of RN on Facebook
  1. Royal Navy
  2. registered nurse
rosin Tweet Definition of rosin Like Definition of rosin on Facebook
  1. (organic chemistry) A yellow-brown resin obtained from several conifers; used in inks, varnishes, adhesives etc; consists of a mixture of terpenoid acids, mostly abietic acid.
rubber Tweet Definition of rubber Like Definition of rubber on Facebook
  1. pliable, Pliable material derived from the sap of the rubber tree; a hydrocarbon polymer of isoprene.
  2. synthetic, Synthetic materials with the same properties as natural rubber.
  3. (italbrac, UK, Australia, Canada regional) An eraser.
  4. (North America) (slang) A condom.
  5. Someone or something which rubs.
  6. (baseball) The rectangular pad on the pitcher's mound from which the pitcher must pitch.
Jones toes the and then fires to the plate.
  1. (North America; plural) Water resistant shoe covers, galoshes, wellingtons.
Johnny, don't forget your rubbers today.
  1. (slang) tire, Tires, particularly racing tires.
Jones enters the pits to get new .
rubberize Tweet Definition of rubberize Like Definition of rubberize on Facebook
  1. To coat with rubber or a similar material.
rubidium Tweet Definition of rubidium Like Definition of rubidium on Facebook
  1. a metallic chemical element (symbol Rb) with an atomic number of 37.
ruthenium Tweet Definition of ruthenium Like Definition of ruthenium on Facebook
  1. a metallic chemical element (symbol Ru) with an atomic number of 44.
rutherfordium Tweet Definition of rutherfordium Like Definition of rutherfordium on Facebook
  1. A transuranic chemical element (symbol Rf) with an atomic number of 104.

Browse the Dictionary

  Words Starting With:
  Words Ending With:
  Words Containing:
  Words That Match:

 Translate Into:
Dutch   French   German
Italian   Spanish
    Show results per page.

Allwords Copyright 1998-2024 All rights reserved.