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->''"Beakers? Of colored liquids? But that means... there's SCIENCE going on here!"''
-->-- RunningGag from the defunct movie review website ''Cold Fusion Video''

When the subject of a TV show includes the use of deadly toxins, radioactive materials, or biological or chemical agents, you can almost be sure SpecialEffects artists will make them look a lot more [[RealityIsUnrealistic interesting than they are in real life]]. This is because the vast majority of chemical compounds are colorless, odorless, tasteless and could easily be substituted with a glass of [[color:blue:water]] or a spoonful of salt. Since that doesn't ''look'' exciting or menacing, they tend to get totally unrealistic spruce-ups.

Radioactive elements tend to have a SicklyGreenGlow, despite the fact that only radium paint does this in RealLife. And even then, it's the zinc sulfide in the paint reacting to high-energy alpha radiation that causes the pale [[color:green:green]] glow, not the radioactive element itself. Pure radium is an ordinary-looking silvery metal. Since radium paint was once used to make glow-in-the-dark watch faces and instrument gauges before the health risks became known, "radioactive = glowing [[color:green:green]]" has stuck in the public mind.

For that matter, acid is almost always depicted [[color:green:green]] and frequently boiling too. While it's true that acid solutions in the real world can vary widely in color from [[color:green:green]] to [[color:red:red]] to everything in-between, the acids most often used for modern industrial purposes (sulfuric and hydrochloric) are colorless and clear. Furthermore, boiling them would not be a tremendously useful or wise thing to do. Incidentally, skin contact with most industrial acids will cause a potentially serious and painful chemical burn; but it won't [[HollywoodAcid dissolve someone instantly to the bone]].

Note, however, [[TruthInTelevision that there are several kinds]] of DeadlyGas in RealLife that ''are'' colorful -- most notably, fluorine ([[color:goldenrod:yellow]]), chlorine ([[color:green:green]]), and bromine ([[color:red:red]]-[[color:brown:brown]]), though bromine is a liquid at room temperature.

Electricity, too, is more colorful and dramatic than in the real world, even more so in animation. Anything electrically charged, such as an electric fence, is more likely than not to light up the surrounding area with crawling arcs of jagged [[color:blue:blue]] fire accompanied by a sizzling noise, even though in the real world such a display requires a charge of tens of thousands of volts and a separation from an electrical ground that is within rather narrow limits. If a person on TV is being electrically shocked, there will almost always be an extremely impressive display of buzzing and crackling arcs of flickering [[color:blue:blue]] fire and perhaps even a display of XRaySparks.

While mains electricity at 100-250 volts is more than capable of killing a human being in the right circumstances, it isn't nearly enough for impressive displays of St. Elmo's Fire.

The center of a nuclear reactor ''does'' glow, but it certainly doesn't pulse up and down—and again it's not green. The glow is called [[http://en.wikipedia.org/wiki/Cherenkov_radiation Cherenkov Radiation]] and it's a pleasing steady blue color. Of course, it's only safe to view that blue glow through water, at the bottom of a "swimming pool" reactor—if you see it in ''air'', and not on the other side of thick leaded glass, then to quote [[http://www.projectrho.com/public_html/rocket/radiation.php Winchell Chung]], "...the good news is you can probably live long enough write your last will and testament. If you write very quickly."

Dropping a chunk of dry ice into a beaker of water will cause it to appear to boil and give off a ghostly white fog; this isn't all that useful (sometimes small pellets of dry ice are used this way in order to exclude air from a container briefly), but it is a staple of the MadScientistLaboratory. If you add a bit of universal indicator to the water, adding the dry ice will make it ''turn red'' and start smoking.

Oddly, the one color you don't often see, but is actually common in laboratories, is hot pink. [[{{Phlebotinum}} Phenolphthalein]] turns bright pink in a basic solution, and is frequently used in acid-base titrations. It will also go red in very strongly acidic solutions, though this is seldom used for anything in a laboratory.

Electronics are not exempt from this either--high-tech machines will often be covered with pretty but seemingly pointless blinking LED lights (which old-school computer types refer to as "[[http://en.wikipedia.org/wiki/Blinkenlights das Blinkenlights]]"), glass pipes full of glowing energy, and meaningless screens displaying bright symbols. Modern technology, especially [[IncrediblyObviousBomb things]] that need to be [[IncrediblyObviousBug covert]], don't usually have these; with the exception of [=MP3=] players.

However, if you go into a lab that works with transition metals, it will be very colorful. It's one of their noted properties.

GratuitousLaboratoryFlasks are the standard container for Technicolor Science in its liquid form; expect to see plenty of examples of the LabcoatOfScienceAndMedicine there as well. See also TechnicolorToxin and ScienceCocktail.



* The University of Leicester once synthesized a krypton compound named "kryptonite" for a lark. It was a colorless crystal with a green light under it, but at least it's fairly harmful (it's a powerful oxidizer), unstable, and contained some ''radioactive'' krypton.

* In ''Film/TheRock'' terrorists threaten San Francisco with VX nerve gas, portrayed as ominous green goo inside glass balls.
* The TropeMaker here would likely be Creator/FritzLang's ''Film/{{Metropolis}}''. The description of the MadScientist's lab in the script stated the laboratory is "as much a place for alchemy as science, a magician's lair."
** Of course, the 'color' part isn't so visible, with the movie being black and white.
** Metropolis also featured the Jacob's Ladder electrical demonstrator, that later became famous as the "science-y" thing in the 1931 Frankenstein.
* ''Film/BackToTheFuture'' plays this straight with the lightning and some effects around the [=DeLorean=], along with showing the plutonium as being bright red.
* Played straight in ''Film/TheNuttyProfessor''. Of course, it ''was'' [[RuleOfFunny a comedy.]]
* Lampshaded in Creator/AkiraKurosawa's ''Dreams''. One character notes in "Mount Fuji in Red" that the clouds of radiation were colored by scientists to act as identifiers for certain elements; instead, people just associated them with hideous radiation and refer to them as "Death's Calling Card."
* In ''Film/CatsAndDogs'', Professor Brody's basement laboratory is wall-to-wall with glass beakers of brightly-colored fluids. (This is for a guy trying to produce a vaccine against ''dog allergies''.)
* In ''Film/TheRockyHorrorPictureShow'', Frank N Furter's lab features a tank that he fills with rainbow-colored chemicals to bring Rocky to life.
* [[AvertedTrope Averted]] in the movie adaptation of Creator/StephenKing's ''Film/{{Thinner}}'', where a gypsy is threatened with a glass of acid that is actually clear.

* Averted and lampshaded in Creator/TerryPratchett's ''Discworld/FeetOfClay''. Vimes is very surprised to find out that arsenic is not green, since that is how he imagined a deadly poison.
** A dwarf who succumbs to poison in ''Thud!'' does salivate green, however.
** Terry Pratchett is very familiar with this trope: when he was press officer for British Nuclear Fuels, he got used to TV journalists bringing their own green smoke and bubbling test tubes so power plants would [[RealityIsUnrealistic look right]].
* One of R.A. Salvatore's [[Literature/TheLegendOfDrizzt Drizzt]] novels prominently featured a ''giant green glowing pool of acid'' sitting in a cave for no reason. Walking above it was perfectly safe, but fall in and you instantly dissolved.
** Salvatore, it should be mentioned, wasn't making this up. Such pools of acid, along with [[ConvectionShmonvection oddly retiring lava]], were staples of the ForgottenRealms Underdark campaign setting he'd been commissioned to write for.
* ''Literature/TheLegendOfRahAndTheMuggles'' has purple haze generated by nuclear fallout. Apparently, the moon can shine through it or something. Yeah...
* The potion in ''Literature/TheStrangeCaseOfDrJekyllAndMrHyde'' starts out red and then turns purple before settling on green.
* Done infamously in ''Literature/{{Twilight}}'': In her world, driftwood fires are blue. Supposedly because of the salt. Salt, for those who don't know, turns fire ''yellow''. At least, it does in RealLife.

[[folder:Live-Action TV]]
* The AppliedPhlebotinum in ''Series/TheFortyFourHundred'' is the neurotransmitter Promicin, which is the neon green of a chemlight in color -- possibly as a ContinuityNod to its discoverer, Creator/JeffreyCombs, who rose to B-Movie stardom wielding nearly identical glowing syringes in the ''Film/ReAnimator'' movies.
* ''Series/DoctorWho'', "Age of Steel": The Cybermen's electric shocks fit the "crawling blue fire" description, both when the Cybermen use them as an attack and when they malfunction.
** The Dalek apparatus in "Evolution Of The Daleks" has both multi-colored liquids in all sort of containers and similar a "crawling blue fire" effect for the lightning.
* In an episode of ''Series/JustShootMe'', Maya gets covered in ToxicWaste while in the sewers and is later found to glow green in the dark. The chemicals are specifically described as "phosphates," none of which have this property in real life.
** The element phosphorus, on the other hand, does at least in its white form. It is also highly toxic and can (and does, though its use is controversial) serve as an incredibly lethal firebomb.
** This property is where the name "phosphorus" comes from, after all.
*** And it does so because it's just slowly ''burns'' in the air.
* The third season premiere of ''Series/{{Heroes}}'', almost in the same breath as NinetyPercentOfYourBrain.
* Also avoided, oddly -- and inaccurately -- enough, in the recent TV film ''Einstein and Eddington''. Scientists are shown testing the 'new' poison gas chlorine on a number of doves. The gas is colorless. In real life, chlorine actually ''is'' green. That's why it's ''called'' "chlorine."
* [[Creator/{{Syfy}} Sci Fi Channel]] [[Film/SyfyChannelOriginalMovie original movie]] ''Megashark vs. Giant Octopus'' featured this trope in the We're Doing Science! portions. The scientists are trying to find a solution to the problem posed by, well, look at the title. This seems to involve large amounts of pouring liquids from test tubes into larger test tubes. All of these liquids are colored. What are they pouring? Why are they pouring it? Something sciency, I'm sure! Later they come up with the idea of making pheromones, so it's back to the lab! More colored chemicals are poured! Finally, success is achieved. How do they know? Because they pour two chemicals together and they change color to glowing green! Obviously, this means they have achieved shark and squid pheromones. Right?
* ''Series/{{Battlestar Galactica|2003}}''. Nuclear missiles always having glowing red tips; although this could be some kind of safety measure so ordnance doesn't get mixed up, even the Cylon nukes have this. Averted though with the disassembled nuclear warhead in Baltar's lab which doesn't glow at all.
** The glowing tips are actually little red lights that are presumably there so the audience can see the missiles at all.
* Subverted subtly in ''Series/TheBigBangTheory'' when Leonard walks into the kitchen to find Sheldon working with beakers full of colored liquid. Turns out he was using flavored Jell-o to make growth media for bacteria.
* In ''Series/TheITCrowd'', Richmond looks after the machines in what is presumably the server room, except he has no idea what the machines do, nor what the flashing lights mean.
* In ''Series/BreakingBad'' the meth starts out as the colorless crystal it is, but later in the series Walt changes how he cooks and gets Blue Meth. Presumably this trope is at least part of the reason for the change.
* ''Series/{{Batman}}'' usually follows this trope, especially with endless colorful variations of KnockoutGas.
* In the old Grenada ''SherlockHolmes'' series Jeremy Brett's Holmes usually had a bunch of these scattered around his desk. Usually they didn't do anything but bubble in the background, but sometimes they were used as a setpiece for solving a crime, or a bit of comic relief.
* Lampshaded in ''Series/{{Arrow}}'', when they open a briefcase containing glowing blue vials.
-->'''Felicity:''' Why does every secret formula have to be a color? Whatever happened to good old-fashioned clear?

[[folder:Video Games]]
* Comes up in ''VideoGame/{{Civilization}} 4'', where the map icon for uranium is a bunch of green rocks. [[JustifiedTrope Of course]], they did have to distinguish it from the silver, iron, and aluminum (yes, I know aluminum and iron wouldn't look like that anyway - y'know what, it's [[MST3KMantra just a game]]).
** Uranium is among the most interesting elements, with a variety of exotic compounds including the bright-yellow, highly corrosive and highly poisonous Uranium Hexafluoride, which meets all the criteria of Technicolor Hollywood science. It's the stuff that the "Bad Guys" want to obtain in RealLife.
*** Also, while uranium ores are mostly black or yellow, they ''could'' be bright green, if some additional impurities are present -- usually gold, which is quite frequent in such ore bodies.
*** TruthInTelevision the minor uranium ore mineral [[http://en.wikipedia.org/wiki/Autunite autunite]] actually is that color. What's more, it [[SicklyGreenGlow glows green]] under UV light. Also,near what is left of Urivan Colorado, the abandoned Uranium mines can be easily spotted by the clear contrast of the green tailings against the red rock in the area.
** ''Civilization 5'' avoids 4's use by making the icon the radioactivity sign, but now the ''terrain'' graphic is green.
* Many futuristic FirstPersonShooter games have pits of deadly green acid and radioactive waste, usually glowing green. ''VideoGame/{{Doom}}'' is the most notable example.
* ''[[VideoGame/Earth2150 Earth 2140]]'' is a notable aversion of the radiation subclass. Radioactive fallout doesn't glow green -- or anything else. It's invisible, and indicated on the minimap with an overlay of black-and-white squares so you can actually tell where it is.
* In the ''VideoGame/CommandAndConquerRedAlertSeries'' series, radioactive areas are recognizable by the green glow. Though while the first game was serious and grim, the other two are anything but.
** In ''VideoGame/CommandAndConquerGenerals'', anthrax comes, in increasing lethality, as green, blue and pink clouds of death. Nuclear radiation, on the other hand, is orange. It still gets reflected by the Chinese Nuke Cannon, which may say "Green... is good." in reference to the ''Red Alert'' series' green radiation.
* ''VideoGame/TimeSplittersFuturePerfect'' plays this for laughs - in one level Cortez and Harry Tipper are trapped in a room filling with green gas, and Tipper comments that green gas is the worst kind.
* In role-playing games with item icons Health potions are often bright red and Mana potions are often bright blue. Poison is green, or if it's particularly deadly, black. Some games may choose other colors. Other types of potions and elixirs come in all manner of colors and shades as well.
** Examples with Red themed health potions and blue themed mana potions include:
** ''VideoGame/WorldOfWarcraft''
** ''VideoGame/CityOfHeroes''
** ''VideoGame/MightAndMagic''
** ''VideoGame/{{Diablo}}''
** ''Franchise/DragonAge''
** ''VideoGame/{{Revenant}}''
** Later ''VideoGame/{{Ultima}}'' games (the ones where inventory item are shown visually instead of as lists) have red health potions, green poison, blue antidotes, and other multicolored fluids.
* The chemistry set in ''VideoGame/TheSims'' yields potions of various bright colors.
* In ''VideoGame/HalfLife1'' radioactive [[InsurmountableWaistHeightFence no-walk zones]] were Radium-glow green and set off the HEV suit's geiger counter. In ''VideoGame/HalfLife2'', the same zones are marked by a dark green non-glowing (yet still geiger-crackling) pit of sludge, and can be traversed safely with the air-boat.
** In ''Half-Life 2: Episode One'', the Citadel's Reactor Core glows blue because of what we can only assume is Cherenkov radiation. However, it is neither a fusion nor a fission reactor; it was built by StarfishAliens from AnotherDimension and generates ''dark energy'', so any assumptions regarding its mechanics are pointless.
* This trope is played straight ''and'' averted in ''VideoGame/{{Borderlands}}''. Corrosive elemental weapons and effects are day-glow green, including the expectorants of Spitter Skags. On the other hand, the obviously acidic projectiles from the Soldier, King and Queen Spiderants are clear fluid in a gel envelope.
* ''VideoGame/LostPig'': "Mysterious bubbling liquids in strangely shaped glassware is the heart of alchemy."
* ''VideoGame/{{Obsidian}}'' contains a puzzle involving test tubes of primary colored chemicals that need to react in a certain way with two secondary colored chemicals. And each chemical is represented by a geometric shape, with the number of each same-colored test tube corresponding to their "sides". Of course, this example is based in the simulated world of someone's dream, so what need is there for logic?

* According to Tom Siddell's [[TheRant Rant]] for ''Webcomic/GunnerkriggCourt'', "...I hereby declare that antigravity is purple and [[PowerGlows glowy]]."
* Colorful chemicals seen in [[http://www.theduckwebcomics.com/The_KAMics/4920837/ this page]] of ''Webcomic/TheKamics''
* Webcomic/{{Narbonic}}: "I find this line of questioning obscene. What manner of mad scientist neglects his flasks of colored liquid?"

[[folder:Web Original]]
* Parodied in the ''WebAnimation/HomestarRunner'' toon, "DNA Evidence":
-->'''Marzipan''': Well, it all started several weeks ago. I came home from my toga-yoga class to find that my house had been broken into and the culprit had left behind some DNA evidence.
-->'''Strong Sad''': What was it? Hair particles? Skin flakes? Blood crispies?
-->'''Marzipan''': No, it was a little test tube just full of green DNA evidence.
-->'''Strong Sad''': Oh! Just like in the movies!
* The eponymous "villain" of ''WebVideo/DoctorHorriblesSingAlongBlog'' has many pieces of colorful liquid-filled equipment in his lab.
* Even the semi-realistic ''WebVideo/Lonelygirl15'' fell victim to this, albeit at a point when the realism was really starting to slack off.
* In ''WebVideo/ItalianSpiderman'' well...
-->'''Scientist:''' It's very red, isn't it?

[[folder:Western Animation]]
* There are plenty of green glowing things at the nuclear power plant in ''WesternAnimation/TheSimpsons'', including Mr. Burns. In "E-I-E-I(Annoyed Grunt)" Plutonium is shown to be a glowing green instead of the real silver color, as well as a fluid instead of a solid (note that most plutonium used in the real world is in a liquid-like powdered form). A Carbon rod used to hold a door on a shuttle closed and seen in the opening is shown as a pale lime-green instead of the real life black.
** Carbon rods are black, so black that carbon is sometimes used to as a pigment. However, it is also brittle. Unless the full length needs to be exposed, the rods are covered in a protective coating, with only a small amount at the end exposed.
* The boiling vat of green acid turns up almost too many times to count in ''WesternAnimation/BatmanTheAnimatedSeries'' and several times in ''WesternAnimation/TeenTitans'' (see also NoOSHACompliance).
* Though it wasn't in a vat, ''WesternAnimation/TheBatman'' lampshaded this when Batgirl said:
--->'''Batgirl''': Why is it that deadly chemicals are always green? Why can't they ever be pink?
* ''WesternAnimation/RickAndMorty'' in general is [[AmazingTechnicolorWorld brightly colored]] and tends to get away with this trope, especially concerning Rick's fantastic inventions and other alien technology. This makes seeing a multicolored test tube set become weirdly jarring because it seems so commonplace by comparison. Best example of this is when Doofus Rick is making ovenless brownies for Jerry.

[[folder:Real Life]]
* Inorganic and Organometallic Chemistry involves attaching small molecules (usually white powders) to the surface of metal ions (usually in clear solutions). The resulting metal complexes are almost always brightly colored and can be anywhere from orange to green to purple depending on the metal and how strongly the chemicals are stuck to it. Admittedly almost all other chemistry involves white powders, clear crystals or colorless solutions.
* Burning salts will give different colors depending on the compound. Table salt burns yellow, copper salt burns blue, and potassium salt burns purple. This is also how they make those nifty little pods that turn campfires weird colors.
* One easy example of this trope is the "[[http://hyperphysics.phy-astr.gsu.edu/hbase/electric/pickle.html Electric Pickle]]" experiment, where a current passed through a pickle actually gets the pickle to glow. Though useless, it is fun to watch. The pickle's been featured in ''Series/{{CSI}}'' and ''Series/BeakmansWorld'', to name a few instances.
* The cover of the Corning catalogue features flasks, cylinders, and beakers with lovely shades of magenta, violet, and jade. Perhaps someone was running tests on various combinations of food coloring.
** High school Chem books love that display. No surprise. However, it can be recreated (without food coloring, that's cheating) with the right bunch of aqueous solutions. Not that there's terribly much use for it, but [[RuleofCool it looks cool]].
* Some very concentrated acids will give off visible fumes in RealLife, which may be either white or, on occasion, a reddish brown.
** [[NamesToRunAwayFromReallyFast Red fuming nitric acid]] is a popular storable hypergolic oxidizer for rocket engines. If you try to store it in a stainless steel container without adding [[OpenSecret hydrogen fluoride]] or something as an inhibitor, it will lose performance and turn green via corrosion of the steel.
* [[http://en.wikipedia.org/wiki/File:Plutonium_pellet.jpg Plutonium-238 pellet glow red with heat]]. The glow is thermal radiation, visible due to high temperature of the pellet. The pellet has been sufficiently insulated from its surroundings so that it has heated up to glowy temperature by its radioactive decay.
** More stable plutonium (other isotopes) is silvery-white, though when it is exposed to air it quickly oxidizes, going from dull gray to pinkish-brown to green.
* Radioactive cesium chloride (used in medical radiotherapy, among other things) is a white powder that emits a faint blue glow.
* Some substances actually do change color when another substance is added. Indicators are an example, best known for changing color depending on the acidity of the solution they're in. For instance, bromophenol blue turns a lovely range between yellows and purples if enough acid is added to bring the pH between 3.0 and 4.6. Methyl orange produces some great reds and oranges, and phenolphtalein, a solution of which is colorless at normal pH, becomes a wonderful reddish purple if enough base (for instance Sodium Hydroxide) is added to bring the pH up to about 9.
** This also works with red wine or grape juice. If you add a strong base (such as ammonia water), the red will disappear since the phenolic pigments in red wine and grape juice are pH-sensitive. Just don't try drinking it afterward...
** [[http://www-users.york.ac.uk/~chem77/pages/Tale_of_2_Radicals.htm Triphenylmethyl radical]] was recognised because solution become yellow when it was created.
* Transition metal compounds are a good example: some familiar examples are potassium dichromate (orange), potassium permanganate (deep purple) and hydrated copper sulfate (blue). Nanoparticle solutions often glow brightly or at least have an interesting color (gold nanoparticle solution is bright pink!); aqua regia (a mixture of nitric and hydrochloric acid) is clear when made but turns orange in a few seconds.
* "Electrons are blue" is a common joke explanation for a phenoenon: things with free electrons whizzing about tend to be bright blue.
** This is because of intrinsic properties of free electron gas, which tends to absorb photons with energies in the "reds" range, thus leaving blue light to scatter and reflect. Most organic dyes are molecules with strongly delocalized electron clouds, and tuning the properties of these clouds is used to achieve a great variety of colors.
* An enzyme disorder known as "Porphyria" can cause your pee to turn a bright purple in color.
** Also, very large doses of vitamin C can turn it orange.
* Perhaps many of those gooey green acids seen in Hollywood have been used to dissolve copper? Anyone who's done any analytical chemistry has probably dissolved copper using concentrated nitric acid. If the unknown sample that you're analyzing has contaminants in it (it usually does), dissolving it in the acid produces a very sickly-looking blue-green solution, sometimes cloudy. As a bonus, the stuff emits a torrent of putrid brown nitrogen dioxide as the copper dissolves.
** Analytical chemistry is overall a bountiful source of flasks of colored liquids. Many tests for the presence of a compound signal a positive result with an obvious color change, while the [[http://en.wikipedia.org/wiki/Beer-Lambert_law Beer-Lambert law]] relates concentration to absorbance of light, making it useful to prepare colored solutions of a substance and stick them in a spectrophotometer. However, as instrumentation has advanced, the field has been moving away from visibly colored solutions to ultraviolet or infrared spectrophotometry, or to solutions so dilute the color is imperceptible.
* A more recent development has been [[http://en.wikipedia.org/wiki/Quantum_dot quantum dots]], metal particles with well defined sizes; the sizes give rise to specific energy transitions, leading to selective re-emission of photons at specific wavelengths. A very cool way to get specific colors, currently being investigated for use within solar cells.
* [[http://en.wikipedia.org/wiki/Black_body Black bodies]] are objects that reflect little or no light, though they can emit their own light when heated up, and they change color depending on their temperature- going from red, orange, yellow, white, and blue. Incidentally, this is how the temperature of stars are measured.
* Most basic lab work of vegetal physiology involves pigmentary extraction. That means that you end up working with bright green liquids.
** One common demonstration of chlorophyll's photon-absorptive properties involves turning a suspension of chloroplasts from green to deep red.
* "Molecular Biology is mostly mixing lots of clear liquids together in glassware (it's mostly disposable plastic nowadays)." That said, assays for DNA often involve fluorescent compounds (more specifically, chemicals that glow under UV only if they're within the DNA structure, quite cool) and in vivo experiments usually involve tagging things with GFP and it's engineered cousins, all of which fluoresce various colors when exposed to the right wavelength of light. The results is that the labs aren't very colorful, but the image data is.
* Chlorine is quite a colorful element. In its common state it's a pale yellowish-green gas, but when cooled and under pressure it becomes a liquid not dissimilar in color to Mountain Dew.
* Neon lights come in multiple colors, though only neon gas itself produces a bright orange glow when introduced to an electric charge. The other colors are made with Helium (pink), Argon (blue), Krypton (white), and Xenon (violet). Hydrogen and oxygen both have a lavender glow, though hydrogen is brighter. Mercury vapor is used in ultraviolet black lights, and sodium vapor is used for the bright yellow color of street lights.
* This can be invoked when news sources want colored solutions for science labs (in one instance, toxicology for Purdey's Proof - Dispatches) in order to make the lab look more 'correct'. This is sadly standard practice for TV around the world - if you're in biology or chemistry, even serious news channels demand beakers full of colored liquids in the background during interviews.
* Histology stains can turn cell parts all sorts of different colors, and some stains, like [[http://www.leica-microsystems.com/typo3temp/pics/POSTER12_13_13f35bdb07.jpg MOVAT's Pentachrome]] stain will make you think that you have dropped some acid before heading into the lab. The stains used in the field of histology chemically react with specific cell components and tissue characteristics. This is so that you can turn these structures different colors, making them easier to see for the purpose of microscopic analysis.
* If different lines on plots in serious science are distinguished by colors, these are often loud colors. More subdued ones are harder to distinguish.
* A popular project recommended in a lot of chemistry books for children involves coating pine cones or other such flammable things with various nitrates in order to make them burn odd primary and secondary colors in a campfire.
* So common is this portrayal of science (especially chemistry) in the media that ''actual'' labs [[TheCoconutEffect will often be decorated]] with some flasks and beakers containing brightly colored liquids, especially if anyone is filming a documentary or propaganda or any kind of educational video in them. One of Kent Hovind's creationist videos, for instance, features some guy in a [[LabcoatOfScienceAndMedicine white lab coat]] standing around holding a glass of bright purple liquid with some dry ice fog coming out of it.
* As far as electronics go, it's common for gaming [=PCs=] and peripherals to have colorful lighting. Custom water-cooling setups can use colored water in the tubes.
* Traditionally, [[http://www.rpharms.com/carboys--cosmetics-and-chemists/carboys---history--colours-and-myths.asp pharmacists would have carboys of coloured liquids]] in their shop windows, so that a largely illiterate population could tell what sort of shop it was.