When a work of fiction creates a new trait of a known element or compound--as opposed to {{Unobtainium}}, which generally just makes up new substances out of whole cloth. Such is usually done in service of the RuleOfCool.

There may be some overlap when real names are used for obviously fictional elements.

May very, very rarely intersect with ScienceMarchesOn, but usually this trope applies either where science has already long since marched on, or some twisted path entirely off the parade route.

Not to be confused with ElementalRockPaperScissors; granted, elements don't work ''that'' way either in RealLife. Compare ParodicTableOfTheElements. MirrorChemistry is often a specific form of this.

It is [[BellisariosMaxim worth bearing in mind]] that several substances in RealLife (especially commercial [[YesButWhatDoesZataproximetacineDo medicines]] and [[HereComesTheScience cosmetics]]) are marketed under names that would make a proper chemist wince, and there's no reason the fictional world should be any different. Kryptonite doesn't have to have anything to do with [[http://en.wikipedia.org/wiki/Krypton Krypton]]... [[TechnoBabble unless they tell you it does]].

Subtropes:

[[index]]
* HairTriggerExplosive
* HollywoodAcid
* {{Unobtainium}}
[[/index]]

----
!!Examples

[[foldercontrol]]

[[folder: Comic Book ]]

* Promethium: (In the real world, it's a radioactive metal with no stable isotopes.)
** In the DCUniverse' it's their version of adamantium.
** In the MarvelUniverse Promethium is used as the name of an extradimensional metal with magical properties.
** In the DCAnimatedUniverse (or at least insofar as ''VideoGame/BatmanVengeance'' is concerned), Promethium is a chemical compound used in cryogenics. It also blows up reeeeal good, hence the name (after Prometheus, bringer of fire).
* "Nth Metal", the substance from which Thanagarian weapons are made in the DCU. Stated in ''JusticeLeagueUnlimited'' to be "transuranic iron", whatever that means.
** If we assume by "iron" they mean "group 8 element on the periodic table", then the first transuranic element would be hassium, which has a maximum half-life of about 10 seconds. Presumably, fights involving Thanagarians are short ones.
* Invoked and subverted in one comic by SelfDemonstrating/TheJoker in a discussion with Catwoman after tagging her with a radioactive isotope tracker hidden in a pie he threw at her. The whole idea was that once she had the tracer on her, the Joker could then play [[HuntingTheMostDangerousGame a twisted game of cat and mouse with her throughout Gotham]] (Hint: She's not the cat...). Subverted in the sense that yes, radioactive isotope tracers can work that way, and invoked in the following conversation:
--> '''Selina:''' "Chemicals don't work that way."
--> '''Joker:''' "My hair is ''green''."
* Both Golden and Silver Age [[ComicBook/TheFlash Flashes]] became empowered thanks to dodgy chemistry.
** Jay Garrick became the Golden Age Flash when he was exposed to "heavy water" (water containing deuterium instead of of hydrogen) fumes. Real heavy water has no effect on humans unless it replaces more than 25% of your body's water, at which point it would just make you sick.
** Barry Allen became the Silver Age Flash when [[LightningCanDoAnything a bolt of lightning]] blasted a rack of crime-scene analysis chemicals onto him. A later {{retcon}} identified the lightning bolt as either a manifestation of the Speed Force or [[StableTimeLoop Barry himself sent back in time at the moment of his death]] during the CrisisOnInfiniteEarths.

[[/folder]]

[[folder:Film]]
* ''Film/{{Evolution}}'' did this for selenium. They {{hand wave}}d it by saying that selenium was to the alien creatures' nitrogen-based biochemistry as arsenic is to carbon-based life forms, because they're in the ''same relative position on the periodic table''. This handwave made it clear that nobody involved in the movie understands the concept of valence electrons[[note]]In real life, arsenic is poisonous because of its relative position to ''phosphorus'', which it can impersonate as far as certain core enzymes are concerned, but it is not quite similar enough that, say, an RNA molecule made with arsenate links instead of phosphate ones will actually fit into a ribosome[[/note]]. Besides, the Rule of Funny dictated they ''had'' to defeat the EldritchAbomination amoeba with gallons of [[ProductPlacement anti-dandruff shampoo]]. There is also the fact that they ''never tested their theory'' before loading tons of the shampoo into a fire truck and going after the amoeba's cloaca.
* The original 1954 ''Film/{{Gojira}}'' movie has [[EyepatchOfPower Dr. Serizawa]] use an invention called the [[ExactlyWhatItSaysOnTheTin Oxygen Destroyer]] to kill Godzilla. In the film, the device worked by dissolving oxygen molecules in the water causing asphyxiation (and also, for some odd reason, dissolving the tissues, bones, etc.) of anything unfortunate enough to get within range of it when it's used. A horrible, horrible way to die. Still, it does leave a LOT of questions on how exactly it ''works''.
** In the original film, it dissolved organic matter completely. In ''Film/GodzillaVsMechagodzilla'' it was retconned to skeletonizing, as they dredged up the first Godzilla's bones to use as the organic frame for Kiryu. Which wasn't the worst effect of the Oxygen destroyer, considering it also allowed hibernating anaerobic creatures to wake up, mutate and become the horrifying anti-life beast [[Film/GodzillaVsDestoroyah Destoroyah]].
* In one of the later films, ''Film/GodzillaVsMechagodzilla'', it's stated that Mechagodzilla is made of [[SpaceX Space Titanium]]. We would like to know how it's different from regular-old everyday titanium, which, by the way, you can already find in outer space (not least because it's a good metal for some parts of our spacecraft).
* In ''Film/StarTrekGenerations'', trilithium is able to stop all fusion inside a star, causing it to implode on itself and then go supernova-- thus destroying the star and all of its inner planets. This involves the same problems as "dilithium," below, plus the added problem that the writers had already given the name "trilithium" to a different fictional substance.
* ''Film/Plan9FromOuterSpace'' asserts that "a ray of sunlight is made up of many atoms," thus making possible the destruction of the universe by solaronite bomb. In RealLife, light is made of photons, not atoms. Even if what they meant was ''solar wind'', a different byproduct of the Sun's fusion reaction, it's composed of ionized particles (atomic nuclei stripped of some or even all of their electrons), not complete atoms. Even if the loose protons and alpha particles somehow picked up electrons, the density alone is so low that it wouldn't be useful.
* In ''Film/SpiderMan2'', Dr. Octavius requires some tritium for his experiments. He obtains it in form of a gray metallic ball. Tritium is gaseous under normal conditions, but it's possible that the gold object is a second layer of containment in addition to the glass ball around it. He also mentions how tritium is one of the rarest elements on Earth. Tritium is an isotope, not an element.
** For some reason, Octavius consistently called it [[InsistentTerminology "precious tritium,"]] as though it was the actual name for the stuff. Perhaps precious tritium is supposed to be different from regular tritium somehow.
* Probably a joke, considering it's ''MarsAttacks''... The Martians must wear space helmets while on Earth because they breathe nitrogen rather than oxygen. However, not only is nitrogen inert, and therefore a poor choice as a gas to breathe, but it's the most plentiful gas in the Earth's atmosphere - i.e. there's more nitrogen than oxygen. However, they don't necessarily die from the lack of nitrogen - if they developed in a world without free oxygen (or other strong oxidizer; if they had to resort to nitrogen...), their "lungs" would probably rapidly oxidize. The atmosphere would be as comfortable to them as an acidic atmosphere to us.
** Except they get around this by chewing gum that's saturated with nitrogen, so the oxygen isn't the problem but the alleged lack of nitrogen.
* In the [[Film/ScoobyDooMonstersUnleashed second live-action movie]], Franchise/ScoobyDoo freezes the Tar Monster with a fire extinguisher. While expanding compressed gas (carbon dioxide, in the case of fire extinguishers) does indeed tend to absorb a lot of heat, it mostly absorbs it ''as it expands'', so this just means you have to worry about [[TongueOnTheFlagpole your hands getting frozen to the fire extinguisher]]. The foam itself isn't cold enough to freeze anything.
* In ''Film/IronMan2'', Nick Fury tells Tony Stark that Tony's been injected with "Lithium Dioxide" in order to remove the effects of palladium poisoning. This implies that lithium has at least four electrons to give up, while it actually only has three. And taking two of them requires more than just some oxygen. This shows one common variant of this trope in Real Life: confusing the type of chemical bonds in a molecule. The wrong part is the ''name'' - it should be: lithium superoxide. And it indeed does exist (at very low temperatures, but still). See Real Life section for the bonding-related difficulties.
* In ''Film/TheRock'', the VX gas description is fairly accurate, save for looking green and melting your skin. It's still very lethal otherwise.
[[/folder]]

[[folder:Literature]]

* In the novel ''[[http://infomotions.com/etexts/gutenberg/dirs/1/8/1/3/18139/18139.htm Ride the Gray Planet]]'', thorium is used as a nuclear fuel, a mild example seeing as it ''is'' used as such in real life, but unlike in the book it [[http://en.wikipedia.org/wiki/Thorium#Thorium_as_a_nuclear_fuel can't be used in nuclear reactors by itself]].
* Quadium is used to power a bomb in ''Literature/TheMouseThatRoared'' [[spoiler:that doesn't actually work due to a mechanical failure in the triggering mechanism]].
* In the Kurt Vonnegut novel ''Literature/CatsCradle'' a single synthetic ice-crystal called "Ice-Nine," formed of ordinary oxygen and hydrogen, is able to freeze all liquid water that it touches, into identical crystals of "Ice-Nine" via chain-reaction--eventually freezing all water on Earth. Polymorphs of water do exist, although there isn't one that has such a high melting point. You can actually build ice sculptures like this by supercooling water and then pouring it around a seed crystal: search [=YouTube.=]
* At one point, the ''Literature/PerryRhodan'' universe ran on the implicit assumption that matter and antimatter would only react with each other if matching elements and anti-elements came into contact. Thus, oxygen + anti-oxygen = boom, but, say, ''nitrogen'' + anti-oxygen = perfectly safe. (The plot revolved around peaceful visitors from an antimatter universe and the spectacular disasters their visits caused.) The initial explanation for why Ynkelonium, a heavy metallic element that ''didn't'' react with antimatter (and also conveniently suppressed such reactions in its immediate vicinity), acted the way it did was that it simply ''had'' no antimatter counterpart...
* In H.G.Wells' ''Literature/TheWarOfTheWorlds'', the Martian's Black Smoke is said to be made of an unknown element that reacts with the Argon in the atmosphere, causing devastating effects on humans. Argon, being a noble gas, is extremely difficult to react and the reaction will never happen in the atmosphere.
* In the ''Literature/{{Lensman}}'' books by Creator/EEDocSmith, an early power source is "allotropic iron". An allotrope is a molecule consisting of one type of atom; most elements have a variety of allotropes with different properties (two allotropes of carbon are graphite and diamond). In the ''Literature/{{Lensman}}'' universe, there's one allotrope of iron that makes it into this hyperdense radioactive liquid that turns 10% of it's own mass into energy over time, making it a good fuel source for spaceships.
** More accurately, the liquid allotrope is used because it's extremely dense, and because it's iron. His "super-atomic" power plants work by ([[{{Technobabble}} somehow or other]]) releasing the entire binding energy content of a nucleus, and as pointed out above, iron has more binding energy in its nucleus than any other element. The liquid is never depicted as radioactive.
** In their conventional model, neutron stars have a crust of polymerised iron. The magnetic fields of the star are so intense that the iron nuclei are stretched, allowing the atoms to arrange themselves into a hyperdense solid that ... well, it wouldn't be very stable outside the conditions you find on a neutron star.
** Also, iron is ''the worst thing in the universe'' to use for nuclear fuel. It ''absorbs'' energy, both to fuse it and fission it. There's a reason iron buildup in stars' cores causes supernovas...
* Similarly to the ''Traveller'' example under ''TabletopGames'', HBeamPiper had [[http://en.wikipedia.org/wiki/Gadolinium gadolinium]] as a key component of his hyperdrive engines in ''Space Viking''.
* Parodied in the Discworld novel ''Discworld/TheFifthElephant'' -- in addition to the four elephants holding up the Disc, there ''may'' have been a fifth that crashed to the Disc surface like a meteor and left behind a special mineral that could be mined ... namely, fat.
** Also, the ''Science of Discworld'' books introduce several elements -- chelonium, elephantigen, deitygen, and narrativium -- that play a crucial role in the Discworld's cosmology and physical sciences.
* Creator/IsaacAsimov heard Creator/RobertSilverberg make an offhand reference to "Plutonium-186" and noted that such an isotope could not possibly exist. This provided the idea that grew into the novel ''The Gods Themselves'', part of which takes place in an AlternateUniverse where that isotope can exist because nuclear forces are stronger.
* In Andrey Livadny's ''TheHistoryOfTheGalaxy'', one novel includes a presentation of a new type of SpaceFighter that uses a matter/[[AntiMatter anti-matter]] reactor to meet its enormous power requirements. The only problem with this is the use of a rare isotope called antitritium specifically because it only reacts explosively with tritium (hydrogen-3) and no other isotope, making it safe to use. While antitritium is not normally synthesized (antideuterium has been for tests) in RealLife, the properties of antimatter mean that antitritium would not make a distinction between tritium and any other particle.
* According to the classic-era Trek novel ''Literature/HowMuchForJustThePlanet'', dilithium does what it does because its crystalline structure extends in 4 dimensions, which is why it can only be mined, not manufactured. ''All'' atoms extend in 4 dimensions, [[Creator/HGWells No instantaneous cubes]], you know.
* Used in-universe in the first ''{{Literature/Foundation}} book. Salvor Hardin asks the ambassador if his planet have any plutonium available for trade, since the reactors on Terminus could use more. When the ambassador brushes the question aside, it tips Hardin off that the ambassador's world has lost atomic power, since otherwise the man would know that atomic power plants haven't used plutonium in millennia.

[[/folder]]

[[folder: Live Action TV ]]
* ''Series/BabylonFive'': Attempts to avert this by claiming that Quantium-40 is an unknown [[http://en.wikipedia.org/wiki/Isotope isotope]] of potassium with unusual properties. Unfortunately, potassium-40 ''does'' exist in real life (albeit in small quantities): It's radioactive but otherwise unremarkable ([[http://en.wikipedia.org/wiki/Potassium-argon_dating except for being a major method of dating rocks]], meaning that it ultimately plays the trope straight....
* ''Series/BattlestarGalacticaReimagined'': A more subtle example than fictional elements: at one point the show attempted to suggest that organic Cylons have eight-membered rings in their biochemistry where humans have six-membered ones, and that [[spoiler: Hera]] has seven-membered ones. For various reasons (look up "aromaticity", and also the geometric ease with which saturated six-membered rings can be formed while keeping the carbon atoms' bonds at the apexes of a tetrahedron) the prevalence of six-membered rings in Earth biochemistry is a result of fairly basic physics about how atoms bond together, and not something arbitrary that can be simplistically changed to create "alien" biology.
** [[FridgeLogic Also such exotic biology would be pretty darn easy to detect.]]
* ''BlackHoleHigh'':
** Featured two of the characters "progressing" through the periodic table, taking on, in turn, the attributes of each element they passed: one's voice becomes high-pitched and squeaky as he passes helium, then fluoresces as he passes neon; the other turns metallic at aluminum, then reeks of rotten eggs as he passes sulphur. The plot becomes a race against time to resolve the situation before one of them reaches plutonium and explodes (The solution is for them to hug as they reach sodium and chlorine respectively, creating stable and benign table salt). It doesn't take too much FridgeLogic to see the problems with this, as several of the elements along the way should have been, while perhaps not as lethal as plutonium, lethal ''enough''. Several of the traits they demonstrated were not traits of the elements ''themselves''.
** And uranium, which does exactly the same thing in human-sized amounts as plutonium, is two elements before it.
** When they were hydrogen an ignition source would create an explosion with the oxygen in the air. If they made it to lithium any amount of liquid water would react violently with the lithium, releasing the hydrogen and heat which would likely cause an explosion.
* ''Series/BreakingBad'': In the episode ''A Crazy Handful of Nothing'', the show takes a remarkable number of liberties with the chemistry of mercury fulminate. For one, it is not a crystal, it is a powder. This can be HandWaved by assuming that Walt's genius-level crystallography skill let him synthesize crystals out of it anyways, but the episode also makes two other notable errors: it vastly overestimates the explosive power of such a quantity of mercury fulminate, and it vastly underestimates the volatility of the compound itself. Mercury fulminate is ''highly'' reactive with heat and friction, which would only be increased in crystal form. It's a miracle the whole bag didn't explode in his pocket (perhaps that's why the episode is named [[FridgeBrilliance ''A Crazy Handful of Nothing'']]).
* ''Series/DoctorWho'': The Ninth Doctor deduces that the Slitheen family are calcium-based lifeforms based on the fact that they [[ToiletHumour emit gases]] that smell like halitosis and instructs Jackie and Mickey to use [[WeaksauceWeakness splashes of vinegar]] to explode Sip Fel Fotch Pasameer-Day Slitheen in a [[LudicrousGibs shower of viscera]]. No part of the above sentence accurately reflects the chemistry of calcium. Or the fact that bad breath is only related to tooth decay in that both are bacterial actions.
* ''Series/{{House}}'': Played on this trope once. In episode 48 (season 3, episode 2), a metal pin is removed from a boy who claimed to be abducted by aliens. House jokes, just for a moment, with Chase about the item being of an unidentifiable metal that might not even be terrestrial. Chase is puzzled and excited for a second, then House tells him immediately it's just ordinary titanium (it was a surgical pin that had been used to set a broken arm and later worked loose).
* ''LookAroundYou'':
** Has a [[http://www.bbc.co.uk/comedy/lookaroundyou/series1/periodic.shtml Periodic Table]] made of [[RuleOfFunny funny]]. (And in context of the show, the chemical symbol for water is not a typo: "H20" [sic] is actually pronounced "aitch twenty".) This is in addition to the borderline insane qualities attributed to basic elements and compounds: sulphur gives you heat vision, iron causes giant scissors to materialize in the sky above you, bumcivilian (aka iron sulphide) soaks up sound waves, calcium is sentient and can melt your face, and nitrogen is the main ingredient in whiskey.
* ''Series/{{Revolution}}'': In "[[Recap/RevolutionS1E12Ghosts Ghosts]]", sulfuric acid is shown being dispensed from a plastic bottle. Sulfuric acid at a concentration high enough to accomplish what Rachel is attempting would oxidize the carbon in the plastic and should only be stored in glass or ceramic containers.
* ''Series/SapphireAndSteel'': The opening narration. Spot the deliberate mistake:
-->All irregularities will be handled by the forces controlling each dimension. Transuranic heavy elements may not be used where there is life. Medium atomic weights are available: Gold, Lead, Copper, Jet, Diamond, Radium, Sapphire, Silver and Steel.\\
Sapphire and Steel have been assigned.
** To be fair, the creator acknowledged that the mistake was there...but RuleOfCool and all.
* ''TheSarahConnorChronicles'': The main characters have to destroy a stockpile of coltan, an alloy which would be used to make Terminator models more advanced than the T-800 (that, being armored primarily with titanium, had a weakness to heat). In real life, coltan is an ''ore'' containing niobium and tantalum and not an alloy. Although, "in-universe" the fact that they used a thermite reaction to "cremate" dead terminators supposedly made of this highly heat-resistant metal is accurate. Thermite reactions are the hottest thing most people can get their hands on quietly (the simplest is rust and the powder from an Etch-a-Sketch (Aluminum)). It also burns through everything else (including steel and concrete) fairly easily.
* ''Series/StargateSG1'':
** Usually tried to avoid this by never clarifying what its exotic materials (naqahdah, trinium) were, compounds or elements or whatever. However, there is one big {{Narm}} for anyone who knows chemistry in the otherwise fantastic episode "The Torment of Tantalus", where both ''a brilliant scientist'' and several godlike {{Precursors}} think that electrons orbit atomic nuclei like planets around a star--something that has not been believed for decades. That could be poetic license (on the part of the characters, not the writers)--this conceit is used to [[LiesToChildren create a universal language anyone could recognize]] if they had a ''very'' basic understanding of chemistry and physics. It's the archaeologist, and not the physicist, on SG-1 who figures out what it's supposed to be, and the "brilliant scientist's" scientific basis dates back to the '30s.
** The episode states that it's the number of ''electrons'', not the number of protons, that defines an element.
** Similarly, a ''Series/StarTrekTheNextGeneration'' episode "Night Terrors" had aliens providing 'one moon circles' as a clue that they needed hydrogen.
* ''Franchise/StarTrek'':
** Features dilithium being used as a power regulator. Normally, dilithium would be a phrase for two covalent-bonded lithium atoms; but ''Franchise/StarTrek'' ascribes it properties that allow it to regulate the matter-antimatter flow without blowing the ship to pieces. In ''Franchise/StarTrek'', the term dilithium is actually short for "2(5)6 dilithium 2(:)l diallosilicate 1:9:1 heptoferranide", a nonexistent compound which was ascribed implausible properties. Dilithium is able to do its job because its crystal structure repels ionized particles in a magnetic field, so it can be used to regulate matter and antimatter streams, thus allowing the reaction to occur at a controlled rate, whilst allowing the resulting "warp plasma" to exit in the direction required to get it to the warp coils in the nacelles. So while not technically a fuel, if a starship has cracked dilithium crystals and no way to replace or recrystallize them, they're sunk.
** Scotty in Star Trek 4 pointed out after they landed in 20th century Earth that "We can't even do that [recrystallize] in the 23rd century." They then proceeded to nick some fuel (actually ''photons'' (!) ) from a nuclear aircraft carrier and ''do just that''.
** The several early episodes of ''ST:TOS'', most notably "Where No Man Has Gone Before", the successful pilot, make reference to the ship requiring ''lithium'' crystals to regulate the warp drive, and indeed the climax of "Where No Man..." takes place just outside the "lithium cracking plant" on Delta Vega. The switch from lithium to dilithium is, [[WordOfGod according to Word of God]], because a number of fans and people associated with the production pointed out that lithium doesn't work like that.
** The story makes use of deuterium and anti-deuterium for powering their ships, though in ''Series/StarTrekVoyager'', they had a strange tendency to forget that it's just an isotope of hydrogen and thus relatively common (less than 1% of all the hydrogen in the universe, but still, there's a ''lot of goddamn hydrogen''; specifically, 75% of the ''entire universe'' is hydrogen). With the technology available to Starfleet, converting protium (standard, neutron-free hydrogen, which is over 99% of all hydrogen) into deuterium is a relatively trivial operation.
** A recurring threat in later episodes of ''Series/StarTrekVoyager'' were the Malon, a race with the [[PlanetOfHats hat]] of environment-wreckers who do so for profit. The "anti-matter waste" produced by Malon technology is highly unstable and terribly dangerous even under safe storage conditions, which makes carting it off and dumping it in someone else's backyard one of the riskiest and most profitable occupations in Malon society. ...never mind that matter/anti-matter reactions result in the total annihilation of both leaving no physical by-products behind.
** In fact, there had been a TNG episode years earlier in which terrorists invaded the drydocked ''Enterprise'' to steal a highly explosive waste product created as the ship's dilithium crystals wore down. This explosive was called "trilithium", but does not appear to bear any relation to the substance in ''Star Trek Generations'' (And Riker doesn't even recognize the name in the latter).
** Even so it was used in an incredibly stupid fashion. Since ''Voyager'' offered a cleaner power source/way to convert the waste into something harmless locally, the garbage man turned it down (GreenAesop ho!) because it would [[ArtisticLicenseEconomics damage the business]] (specifically "digging holes" variety) of [[TooDumbToLive slowly poisoning himself carting the shit out to the middle of nowhere]]. [[FridgeLogic Instead of taking the technology building a station much closer to home]], then using the tech and making a mountain of money due to lowered shipping costs and [[NoOSHACompliance not killing your employees all the time]].
** "Duranium-235" occasionally referenced here and there ("duranium" being a strong building material used for most ''sane'' space vessels in the TrekVerse) implies an isotope of an element... thing is, if there is an interesting property of any isotope with atomic weight 235 (protons and neutrons like to band together in particular configurations, making an atomic weight very likely to give away what element the atom is), it's almost certainly good ol' uranium (U-235 being the isotope of uranium prized for its fissile capabilities). If "duranium" is instead a future term for "depleted uranium" (a common fan theory; canon avoids clarification), well, that would be U-238.
** As of ''[[Series/StarTrekVoyager Voyager]]'' season 1, there are supposedly 246 known elements (and in the episode where this is mentioned, they discover the next one). The ones unknown to modern science seem to have new and interesting properties, but the upper limit of the transuranic elements science has been discovering lately are invariably so extremely radioactive that they decay into more normal and stable elements very quickly. While fictional subatomic particles to differentiate things a bit more could patch up this outlandishly high number of elements, such an explanation hasn't been offered... to date, anyway. (To be fair, the episode in question with the 247th element pays lip service to a "stable, transuranic element inside a natural environment" being "a first", and leaves the atomic mass at a vague "over 550", but such properties in a freakishly heavy atom are unlikely, to say the least.)
** No discussion of the Trek universe's chemistry and physics would be complete without the [[http://www.midwinter.com/~koreth/particles/ list of particles in Star Trek]].
** James Doohan, in order to provide consistent answers to fans as to the inner workings of the ''Enterprise'', actually put together his own 'cheat sheet' based upon his understanding of science (he had attended a technical school where he excelled in math and science prior to his military service and acting career). During the later Trek series, both Jonathan Frakes and Robert Beltran asked the writing staff for a similar 'cheat sheet', but were disappointed to find out that by that point the science of ''Star Trek'' was being made up as the writers went along without even any internal consistency (much less accuracy to real-life).
** In one episode of ''Voyager'', a world made of water is in danger because their "oxygen mining" activities are increasing the density of the water. You can't increase water density by removing the oxygen from it....
* ''TalesFromTheCrypt'': There's an episode in which an ulcer-plagued soap-maker is murdered by his wife, who dumps his body in one of his rendering vats and turns him into a stack of bath products. She uses one of these soap bars in the shower, only to be fatally burned by the residual acid from his stomach ... which is impossible, as turning fats into soap requires adding enough lye to give it a neutral to ''alkaline'' pH.
* In season 4 of the TV show ''Alias'', one episode features a substance called Ice Five, which is functionally identical to Vonnegut's Ice Nine.
[[/folder]]

[[folder: Table Top Games ]]

* In the ''{{Traveller}}'' classic TabletopRPG the rare earth element lanthanum was a critical material used in constructing [[FasterThanLightTravel jump drives]]. [[ScienceMarchesOn Assuming faster-than-light travel is possible]], this may actually prove to be true, but it would be more accident than prophecy.
* In ''TwentyThreeHundredAD'', from Game Designer's Workshop or GDW the element tantalum is used in "stutterwarp drives," the type of FTL employed in that universe. Given the importance of interstellar travel, acquiring and ensuring the security of tantalum supplies is an important strategic consideration.
* According to the ''Shadowtech'' sourcebook for ''TabletopGame/{{Shadowrun}}'', Ruthenium-based polymers are used in the production of cloaking suits, which can take input from several cameras and automatically change colors to hide the wearer. Ruthenium is chemically part of the platinum group and is actually very useful and versatile (as, in conjunction with other materials, a hardener, a superconductor, and a catalyst in creating certain alloys), and ''can'' actually ''absorb'' light very efficiently, but in a method useful for solar panels, not cloaking devices.
* ''TabletopGame/{{Warhammer 40000}}'':
** Promethium is also used as flame(throwe)r fuel. At least in this case it's made explicit that "promethium" is used as a catch-all term for this type of fuel, and isn't actually referring to the element.
** Its use of "depleted deuterium" in bolter rounds is particularly bad science: you can't even ''get'' depleted deuterium as it's a stable isotope. Apparently this was a spelling/editing error; the writers are still kicking themselves over it.
** Standard bolter rounds (and apparently some other forms of armor-piercing ammunition) are tipped with "diamantine", implicitly some form of super-hard metal or compound, but drawn to basically look like a sharp-pointed diamond, tip out, which may or may not actually be what it is. It was designed when Terran weaponsmiths realized that armor existed which couldn't be penetrated by any known weapon. Of course, this also meant they [[LensmanArmsRace had to develop even stronger armor, which only lead to stronger weapons]], from increasingly bizarre combinations of Unobtanium that make modern chemists' and physicists' heads explode.
** Meltaguns are pretty iffy too. There's two separate descriptions on how they work (some sources say these are two different weapons that share the same function and thus are both commonly known as meltaguns). One version is that they cause thermal agitation, cooking the target alive. This explanation doesn't really break any laws of physics (although you'd need a lot of energy to heat metal to the melting point, and you'd have to keep the heat from dissipating), but the other makes considerably less sense, claiming the weapon fires a mixture of pyrol-petroleum jelly that has been forced to a sub-atomic stage and then ignited.
** [[http://en.wikipedia.org/wiki/Neutronium Neutronium]] is likely real, but it can't exist outside of a neutron star. It would immediately decompose into normal matter, along with a lot of antineutrinos and gamma radiation.
* ''RuneQuest'' has mineable bronze. There is a form of bronze that might occur in an ore form—[[http://en.wikipedia.org/wiki/Arsenical_bronze arsenical bronze]]. Of course, the fumes from working with it are toxic, which is theorized to be why several smith-gods (e.g. Hephaestus) are crippled.

[[/folder]]

[[folder: Video Games ]]

* For examples involving weapons and armor (especially prevalent in {{RPG}}s), refer to the ElementalCrafting sub-trope (aka RPG clichè #144).
* In the ''{{Traveller}} 2300'' game, tantalum was a vital element in the stutterwarp drive.
* ''{{X-COM}}: UFO Defense'' has [[ImportedAlienPhlebotinum Elerium-115]] being one of the most important items to collect in the game. The 115, in this case, is most likely a reference to [[http://rationalwiki.org/wiki/Element_115 the conspiracy theories about element 115]], known today as ununpentium, as it is used in much of the same manner. (Unfortunately for them, [name]-[number] notation usually denotes an isotope, and the number is its ''atomic mass'', not element number.)However, since the game was made ten years before ununpentium was synthesized, it's forgivable. Considering that Elerium is highly radioactive and looks a lot like Bismuth, which is one row up, they did a pretty good job.
* In old versions of ''VideoGame/DwarfFortress'', bauxite was the only rock that magma won't melt, when there should have been many others. This is because the melting points for stones that should melt at higher temperatures weren't programmed in, and were left at the default temperature. This has been fixed in version 0.31.01 and up - nearly 30 types of stone, 6 of which form entire layers, are now magma safe.
* Tiberium from ''VideoGame/CommandAndConquer''. However, like kryptonite in ''SupermanReturns'', it's stated to be a compound rather than an element - ''Tiberian Dawn'' gives it as 42.5% phosphorus, 32.5% iron, 15.25% calcium, 5.75% copper, 2.5% silica (itself a compound), 1.5% unknown. Tiberium crystals do absolutely nothing and their prime property is that they're valuable because of the high concentration of valuable elements. Now, the Tiberium ''plant'', [[BodyHorror on the other hand...]] By the time Tiberium Wars comes around all the Tiberium on the planet has changed. It is no longer a plant but just a crystal lattice made of (green or blue) protons held together by exotic particles. When atoms brush against the lattice it smashes them to pieces and steals their protons, turning it into more Tiberium. This has caused the majority Tiberian-based mutants to die off.
* ''{{VideoGame/Singularity}}'' revolves around the key to sending things backwards and forwards in time being the mysterious "Element 99". As you can imagine, [[http://en.wikipedia.org/wiki/Einsteinium Einsteinium]] does not work that way. The scientists in game had discovered the element well before synthesizations of such transuranic elements existed. It's therefore feasible, but not likely, that the scientists would have just given it an element number way past anything on the then-smaller table.
* ''VideoGame/TheSims 3'':
** It allows sims to collect mineral ores. In order of worth: Iron, Silver, Gold, Palladium, and Plutonium. In Real Life, Plutonium is a whitish, radioactive metal that occurs as a result of Uranium decay. Therefore, Plutonium is dangerous and only occurs in nature when coupled with uranium ore. In The Sims 3, Plutonium is a green, naturally occurring ore that sims can carry around forever with no ill effects.
** For that matter, palladium is intermediate in price between silver and gold rather than being more valuable than the latter; [[RuleOfCool the same justification probably applies.]]
** Funnily enough, you can get Tiberium, which has some interesting properties - when in your backpack, it causes your sim to develop Tiberium sickness after a while and can even kill him/her. If left alone on the ground, it will develop from "ore" to a crystal and will eventually duplicate itself. It also makes funny noises.
** You can also get solid ingots of mercury, which are yellow-ish in color
** And then you have metals like "[[{{Mummy}} mummitomium]]", "woohooium", "compendium", and "supernovium", the latter two of which are found by transfiguring a number of different metals together.
* ''VideoGame/WorldOfWarcraft'':
** One of the zeppelin manager {{NPC}}s tells you that the craft may explode "like a huge helium bomb." Then again, [[MadeOfExplodium it was made by a goblin]].
** Thorium is another example. In the real world it's a grayish radioactive metal, but in ''VideoGame/{{Warcraft}}'' world it's a greenish metal that was used to make high quality armor at lv.60. Whether or not you'd want to wear a potentially radioactive pair of platemail pants is questionable. The game notes explicitly state that the "thorium" of Azeroth is entirely unrelated to real-world thorium.
** ''VideoGame/WorldOfWarcraft'' also has various dropped items of jewelry made out of Thallium, which is both unattractive and direly toxic.
*** The 2nd expansion adds cobalt as a base for armor and weapons, which would probably not be a good idea due to the potential toxicity of its compounds (cobalt metal isn't much more toxic than iron - but it is hard to purify) and tendency for cobalt ores to contain arsenic.
*** It's also cobalt-blue, exactly like metal cobalt isn't. (The metal is shiny grayish-silver, like most transition metals.)
*** There is also Titanium, which is classified as a rare metal. In real life Titanium ore is extremely common (though turning it into usable metal is another story), much more so than cobalt. Again, in the game it could be that Titanium is something completely different than its real life counterpart. Particularly since Titanium can be transformed into Titansteel, a material with an obvious connection to the [[PhysicalGod Titans]] who created the world.
** Surprisingly, copper, tin, and iron -- the first three tiers of minerals a character can mine -- all behave like their real-world counterparts. Except for the fact that armor made out of them can increase their wearer's strength and agility. Silver and gold, likewise, are pretty mundane as mined minerals; though for some strange reason, the vendor value for a ''bar'' of smelted gold is less than 1/10 of a gold coin -- but then again, there's inflation.
* ''MapleStory'' has Bronze Ore. Bronze, being an alloy of copper (which exists on its own) and tin, doesn't actually come from rocks. While this is probably just an honest misunderstanding, Steel Ore is utterly inexcusable.
** Not as much as you think. There are (or at least were) mines near Toledo, Spain that produced natural steel, and in the Bolivian Andes, copper miners sometimes come across (very small) veins of natural bronze. [[RealityIsUnrealistic Truth and fiction]] are very hard to tell apart at times.
* ''RuneScape'' also uses Promethium as a metal. It is reddish and apparently incredibly resilient, making the best armour players can make with their own forge and hammer. Definitely not radioactive, definitely not unstable.
* In the ''VideoGame/{{Crusader}}'' series, the Silencers' armor is made from polonium. Who knew that a soft, self-heating, unstable, [[http://en.wikipedia.org/wiki/Polonium#Famous_poisoning_cases toxic, radioactive]], reactive element would be good for making ''armor''?
* ''VideoGame/DeadSpace'' treats thermite as an explosive that blasts away a barrier made from scrap, while it actually behaves a lot more like an extremely hot liquid that melts through anything. Just slapping a pack to a vertical steel plate and igniting it would only result in the whole thermite pouring down the plate to the floor and only leaving a scorch mark on the plate.
* The gnosis from ''VideoGame/{{Xenosaga}}'' are made from sodium chloride or, in other words, plain salt. Anything they touch that also happens to be organic will either turn into salt or a gnosis (Still salt, but the ''moving'' kind.) Added bonus for being able to merge with mechs, becoming some sort of hybrid in the process. Don't ask how it works, even the main cast don't understand it.
** Hermetic Alchemy is just one of the eight or nine systems of esotericism that series plays with; in alchemy, salt symbolizes the "bitterness" of the first stages of self-knowledge, i.e., well, Gnosis. The Gnosis also seem to be associated with various kinds of resentment or obsession, both also salt-aspects in alchemy.
* ''[[VideoGame/AmnesiaTheDarkDescent Amnesia]]'' and its epic fail of combining aqua regia, orpiment, cuprite, and calamine all together[[note]]no idea how much of each, which one goes first, etc.[[/note]] to create simply [[HollywoodAcid "acid"]]. No, the pH isn't known either.
* ''VideoGame/TeamFortress2'' gives us Australium, an element [[CaptainObvious only found in Australia]]. The fact that overexposure to Australium leads to TestosteronePoisoning says a lot about accuracy in this game.
* According to the AtelierSeries, a vial of green and a couple of apples somehow creates pie. With crust and pan included, to boot. Want another flavor, or sprinkles or something? Toss in a hunk of metal too.
* The models for most [[TheFederation Argon]] fighters in the ''[[VideoGame/{{X}} X-Universe]]'' games are [[UsedFuture fairly beat-up]], including the odd spot of rust. [[SpaceDoesNotWorkThatWay Last time we looked, rusting required oxygen to be present.]]
* Played with within the ''Franchise/FinalFantasy'' series. Several games have Gold equipment, which would be too heavy and soft to be of any practical use, so most modern games backpedal on this, saying it is gold plated, trying to HandWave it. However, ''VideoGame/FinalFantasyIII'' avers it once and for all in the Gold Manor with Gold Swords you find there have an attack power of ONE. However, they get some worth as you can sell them for a premium.

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[[folder: Western Animation ]]

* It's common in cartoons for gems to ''glow'', seemingly under their own power. A particularly silly example is from [[http://www.youtube.com/watch?v=EafUM5_B6fE this Popeye short;]] a small emerald ''lights up a room.''
* Gold commonly emits "glow" lines in cartoons to denote its shininess. But some animators made gold objects ''actually glow''. Like the ''TinyToons'' episode "Journey To The Center Of Acme Acres".
* ''TheSimpsons'':
** On an episode, Homer was being coaxed to memorize the periodic table, to which he responds that he'll just write it on his arm. The response: "Including all KNOWN lanthanides and actinides? Good luck!" Finding new lanthanides and actinides is impossible, like [[TheInvisibles finding new letters in the alphabet.]] Blame Glenn Seaborg and co, who filled in most of that gap of the periodic table in the '50s. The last was found in the 1960s, so perhaps the writer was just a baby-boomer who hadn't kept up with developments.
** Parodied in an episode of the Simpsons where the classroom had a periodic table "sponsored by Oscar Meyer" with Bolognium (atomic weight: "delicious" or "snacktacular")
* ''WesternAnimation/PhineasAndFerb'':
** On one episode the MacGuffin is an element called "Pizazzium Infinionite," which is shown on the periodic table as element 104. In real life this spot is already taken by rutherfordium, which is significantly less cool than Pizazzium apparently is.
** The show uses "Pizazzium" and "Pizazzium Infinionite" interchangeably. In reality, "Pizazzium Infinionite", if it existed, would be a ''compound'' made up of Pizazzium atoms/ions and whatever element(s) "Infinionite" atoms/ions is comprised of (and therefore does not belong on a periodic table of ''elements'').
* An {{Anvilicious}} episode of ''TransformersGenerationOne'' featured a naturally-occurring lake of electrum, a substance which inexplicably rendered Transformers invulnerable when they coated themselves with it. Not only would electrum be useless for this purpose, but no such mixture of gold and silver could be a liquid at normal outdoor temperatures. Hence, the pretty woodland glade which [[GreenAesop gets trashed in the quest for invulnerability]] should've been flash-fried long before the robots discovered it.
* In the pilot miniseries of ''WesternAnimation/{{Inhumanoids}}'', D'Compose is freed from a massive chunk of amber, then later trapped in a pit of liquid amber and re-imprisoned. While real amber softens and gets sticky when heated, it generally catches fire before it reaches its melting point. If the Redwoods had called their trap a ''resin'' pit, it wouldn't be this trope; as it is, you'd think a bunch of walking trees would know the difference between solid amber and liquid pine resin.
* Kryptonite is {{Unobtanium}} and, to an extent, can behave however the writers want. But it's still a radioactive mineral. In the DCAnimatedUniverse movie ''Superman & Batman: World's Finest'', dissolving kryptonite in acid means it's "disappeared", and Superman is back to full strength. In the real world, dissolving radioactive isotopes in acid leaves you with a radioactive acid.
** It will remain radioactive, but the change in the structure might somehow affect the radiation, making it harmless to Superman.
* In ''WesternAnimation/Ben10AlienForce'', Quartz is apparently very useful for both Time Travel and FTL Wormholes.

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[[folder:Other]]

* Plutonium and uranium get this a lot.
** Their abilities are quite often exaggerated and made up, and they're usually depicted as [[TechnicolorScience glowing and green]], not the dull gray they actually are.
** It is also depicted as being far less ''flammable'' than it actually is. Uranium and Plutonium metal are both pyrophoric and can burn when exposed to air at room temperatures. This is why depleted Uranium is the substance of choice for anti-tank projectiles as they not only punch through the armour, but [[RuleOfCool also ignite whatever's inside]]. This is also why early nuclear reactors using Uranium metal had a tendency to [[http://en.wikipedia.org/wiki/Windscale_fire catch fire]]. Many early reactors used graphite blocks for a moderator, compounding the problem, as proved by Chernobyl. This is an issue because of how ''brittle'' uranium is in its metallic form. Pyrophoric means that it ignites very easily (bordering on spontaneously) when very finely divided. Because of how brittle it is, a slug of depleted uranium will likely shatter on impact into thousands, or possibly even ''millions'' of microscopic shards, more than sufficient for its pyrophoric nature to rear its ugly head.
*** And if they ''don't'' catch fire, you're still going to die a painful death. Even a couple specks of uranium or plutonium entering your lungs is a gruesome, bloody death sentence. No one without a hazmat suit should dare touch it in real life, which obviously isn't convenient for fiction.
* Alchemy. Until the 17th century or so, current views of science indicated that all matter was made out of a few 'elements' or 'qualities' (fire, air, water, and earth, most of the time). It was completely plausible, from their point of view, to change one form of matter into another by finding methods which would speed up the natural process of transmutation. Quite a few of the fathers of early science, such as Isaac Newton and Robert Boyle, were also practicing alchemists. The problem with Alchemy was mostly due to scale and the fact that it still had some lingering "magical" notions. Some things were right in front of them the whole time, like with the universal solvent - turns out it's water. Nobody wanted to admit that, they just kept looking for that cool acid that dissolves everything instantaneously. Thus, alchemy isn't a science. Its IdenticalGrandson, chemistry, is.
* Many people in RealLife like to think of Titanium as some sort of fantastically strong [[{{Unobtainium}} Uber-Metal]] (''Anime/MobileSuitGundam'', we're looking right at you) when in reality it's actually no stronger than steel, it's just lighter and rust-proof. But the AWESOME thing about titanium is that no known human is allergic to it, unlike any other metal, so it can be used for dental implants and orthopedic plates, pins, and screws. So from a sci-fi standpoint, it is the one metal you can put in your body permanently and not have to worry about. Adamantium, anyone? Not only that, but for no known reason human bones will graft onto Titanium quickly and easily. THIS is a big reason it's so great for implants, plates, and pins.
** However, because it cannot be melted in air (it will burn before it melts) it cannot be welded in air, and it won't take solder.
** As for Gillette, Schick (and Wilkinson Sword) making razors out of titanium, it's partly because (as has been mentioned) no-one's allergic to the stuff, but mainly because it's more resistant to rust.
* Speaking of diamonds, many people still seem to mistake their hardness for durability. If you ask a random person which breaks if you hit a diamond with a hammer, way too many pick the hammer. In fact, just because diamonds are ''hard'' doesn't mean that they can take any kind of punishment. Window glass is harder than a pillow, but a pillow still survives strikes that destroy the glass. If you hit a diamond with a hammer, you will get lots of little, sharp diamond shards and a hefty bill from the diamond's owner. Just because you can't ''scratch'' a substance doesn't mean you can't break it.
* Greg of ''Webcomic/RealLifeComics'' once [[http://www.reallifecomics.com/archive/040106.html claimed]] that truck is made of '''[[ShapedLikeItself truck]]''', which he then attempted to insist was an element that appears on the periodic table [[CloudCuckoolander between beer and pretzels]].
* [=ThinkGeek=] sells [[http://www.thinkgeek.com/homeoffice/kitchen/a3f6/ salt and pepper shakers]] with the purported chemical formulae used to identify each one. As the main component of edible table salt, "[=NaCl=]" is acceptable to show which one should contain salt. However, "P[[subscript:e]]+(P[[subscript:e]])r" is a stretch, especially so at an online store frequented by geeks and those with more than a passing interest in basic chemistry. Surely "C[[subscript:17]]H[[subscript:19]]NO[[subscript:3]]", the molecular formula for piperine, would be more apt; while piperine is only one of many constituents of black pepper, it is the compound responsible for the pungent flavouring.
** Except it is explicitly stated that they couldn't fit the formulas of all the chemicals onto it, so they instead used P[[subscript:e]]+(P[[subscript:e]])r.
** Also, considering the site, Probably RuleOfFunny and JustForPun come into play. The funny thing about many geeks is they understand that that Pe+(Pe)r is an amusing pun on pepper, not the site being serious. Since, you know, the visitors are not actually morons.
** Maths geeks would of course prefer it to be written P[[subscript:e]](1+r).
* DanBrown has stated several times that, in his opinion, antimatter is the future of energy supply. He fails to realise that what he's describing is the molecular equivalent of a perpetual-motion machine -- making antimatter requires a lot more energy than it releases (probably ''vastly'' more, as at present where it can only be found briefly in particle accelerators). It might one day be a high density fuel source but only if energy became dirt cheap anyway and we didn't have to worry about our energy supply.
* You know those commercials that are promising financial compensation and legal representation for people affected by certain drugs or medical implants? Well now they're really scraping the bottom of the barrel it seems, because two of the most current advertise financial compensation for heart valve issues caused by the drug Phen-fen (or Phenfluramine, which is already known to cause heart valve issues) and liver dysfunction following the use of acetaminophen (a pain-killer already known to cause liver failure and dysfunction with overuse despite the fact every painkiller containing this drug has to warn about its effects under the Drug Warnings)! So not only do the commercials fail Chemistry forever, they also fail Pharmacology forever!
* A quite common problem with chemistry is: confusing the ways the atoms are bonded together. Especially covalent and ionic bonding.
** Example: ask anyone with some basic chemistry knowledge what would you get when potassium reacts with oxygen. Will it be oxide (K[[subscript:2]]O), peroxide (K[[subscript:2]]O[[subscript:2]]) or superoxide (KO[[subscript:2]])? Most people will point at oxide (4K + O[[subscript:2]] -> 2K[[subscript:2]]O), and will add that superoxide is unlikely to even exist (potassium has one valence electron, but in such case it would require pulling out four electrons, which requires way more than just oxygen). Which would be true - if the bonding would be a covalent one. But all metal oxides have ''ionic'' metal-oxygen bonds. In such case, a reaction K + O[[subscript:2]] -> KO[[subscript:2]] is the simplest one (it merely requires a single electron to jump from potassium to oxygen), while the seemingly obvious 4K + O[[subscript:2]] -> 2K[[subscript:2]]O is very unlikely (it requires an exchange of four electrons and, more importantly, splitting the O[[subscript:2]] molecule into single atoms - which requires a significant amount of energy). In reality, burning potassium in oxygen results in a mixture of potassium superoxide and peroxide; the oxide does exist, but is acquired in a different way (by reducing peroxide with excess potassium).

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