“E550” redirects here. For the Italian locomotive, see by atmospheric changes”.[8][9] Von Wagner distinguished FS Class E550. soda, potash, double (soda and potash), and fixing (i.e., stabilizing) as types of water glass. The fixing type was Sodium silicate is the common name for compounds “a mixture of silica well saturated with potash water glass and a sodium silicate” used to stabilize inorganic water with the formula Na2(SiO2)O. A well known member of this series is sodium metasilicate, Na SiO . Also known color pigments on cement work for outdoor signs and mu- 2 3 rals. as waterglass or liquid glass, these materials are avail- able in aqueous solution and in solid form. The pure com- positions are colourless or white, but commercial samples are often greenish or blue owing to the presence of iron- 2 Properties containing impurities. They are used in cements, passive fire protection, tex- Sodium silicate is a white powder that is readily solu- tile and lumber processing, refractories, and automobiles. ble in water, producing an alkaline solution. It is one of Sodium carbonate and silicon dioxide react when molten a number of related compounds which include sodium to form sodium silicate and carbon dioxide:[1] orthosilicate, Na4SiO4, sodium pyrosilicate, Na6Si2O7, and others. All are glassy, colourless and soluble in wa- ter. Na2CO3 + SiO2 → Na2SiO3 + CO2 Sodium silicate is stable in neutral and alkaline solutions. In acidic solutions, the silicate ion reacts with hydrogen Anhydrous sodium silicate contains a chain polymeric ions to form silicic acid, which when heated and roasted anion composed of corner shared {SiO4} tetrahe- 2− [1] forms silica gel, a hard, glassy substance. dral, and not a discrete SiO3 ion. In addition to the anhydrous form, there are hydrates with the for- mula Na2SiO3·nH2O (where n = 5, 6, 8, 9) which contain the discrete, approximately tetrahedral anion 3 Production 2− SiO2(OH)2 with water of hydration. For example, the commercially available sodium silicate pentahydrate Sodium silicate is commonly manufactured using a reac- Na2SiO3·5H2O is formulated as Na2SiO2(OH)2·4H2O tion in liquid phase or in solid phase. Both processes use and the nonahydrate Na2SiO3·9H2O is formulated as alkaline and quartz sand as raw materials. [2] Na2SiO2(OH)2·8H2O. In industry, the various grades of sodium silicate are char- 3.1 Liquid phase acterized by their SiO2:Na2O weight ratio (weight ratios can be converted to molar ratios by with A mixture of caustic soda, quartz sand, and water are pre- [3] 1.032), which can vary between 2:1 and 3.75:1. Grades pared in a mixing tank, then fed into a reactor, where with this ratio below 2.85:1 are termed 'alkaline'. Those steam is introduced. The reaction is with a higher SiO2:Na2O ratio are described as 'neutral'. n SiO2 + 2 NaOH → Na2O•nSiO2 + H2O

1 History 3.2 Solid phase (thermal process)

Sodium carbonate and sodium sulfate melt at tempera- Water Glass[4] was defined in Von Wagner’s Manual of tures far below that of silica. (<900 °C vs >1600 °C) Chemical Technology (1892 translation) as any of the sol- Either is melted, and silica dissolved into the molten ma- uble alkaline silicates, first observed by Jean Baptist van terial, where it reacts to form sodium silicate. Helmont circa 1640 as a fluid substance made by melt- ing sand with excess alkali.[5][6] Glauber made what he termed “liquor silicum” in 1646 from potash and silica.[7] Na2CO3 + x SiO2 → (Na2O)•(SiO2)ₓ + CO2 Johann Nepomuk von Fuchs, in 1818, obtained what is now known as water glass by treating silicic acid with an 2 Na2SO4 + C + 2 SiO2 → 2 Na2SiO3 + 2 SO2 alkali, the result being soluble in water, “but not affected + CO2

1 2 4 USES

4 Uses sodium silicate (doubly negatively charged anion accom- panied by two sodium cations) and they subsequently ag- [3] In 1990, 4M tons of alkali metal silicates were produced. gregate. This process is called coagulation/flocculation. The main applications were in detergents, paper, water [3] treatment, and construction materials. 4.6 Refractory use

Water glass is a useful binder of solids, such as 4.1 Adhesive vermiculite and perlite. When blended with the afore- mentioned lightweight aggregates, water glass can be used The largest application of sodium silicate solutions is a to make hard, high-temperature insulation boards used [3] cement for producing cardboard. When used as a pa- for refractories, passive fire protection and high tempera- per cement, the tendency is for the sodium silicate joint ture insulations, such as moulded pipe insulation applica- eventually to crack within a few years, at which point it tions. When mixed with finely divided mineral powders, no longer holds the paper surfaces cemented together. such as vermiculite dust (which is common scrap from the exfoliation process), one can produce high tempera- ture adhesives. The intumescence disappears in the pres- 4.2 Drilling fluids ence of finely divided mineral dust, whereby the water- glass becomes a mere matrix. Waterglass is inexpensive Sodium silicate is frequently used in drilling fluids to sta- and abundantly available, which makes its use popular in bilize borehole wells and to avoid the collapse of bore many refractory applications. walls. It is particularly useful when drill holes pass through argillaceous formations containing swelling clay minerals such as smectite or montmorillonite. 4.7 Dye auxiliary

Sodium silicate solution is used as a fixative for hand dye- 4.3 Concrete and general masonry treat- ing with reactive dyes that require a high pH in order ment to react with the textile fiber. After the dye is applied to a cellulose-based fabric, such as cotton or rayon, or onto silk, it is allowed to dry, after which the sodium sili- Concrete treated with a sodium silicate solution helps to cate is painted on to the dyed fabric, covered with plastic significantly reduce porosity in most masonry products to retain moisture, and left to react for an hour at room such as concrete, stucco, plasters. A temperature.[10] occurs with the excess Ca(OH)2 (portlandite) present in the concrete that permanently binds the silicates with the surface making them far more durable and water repel- 4.8 Niche and hobby uses lent. It is generally advised to apply this treatment only after the initial cure has taken place (7 days or so depend- 4.8.1 Passive fire protection (PFP) ing on conditions). These coatings are known as silicate mineral paint. Sodium silicates are inherently intumescent. They come in prill (solid beads) form, as well as the liquid, water glass. The solid sheet form (Palusol) must be water- 4.4 Detergent auxiliaries proofed to ensure long-term passive fire protection. Standard, solid, bead form sodium silicates have been It is used in detergent auxiliaries like complex sodium used as aggregate within silicone rubber to manufac- disilicate and modified sodium disilicate. The deter- ture plastic pipe firestop devices. The silicone rubber gent granules gain their ruggedness from a coating of [3] was insufficient waterproofing to preserve the intumesc- silicates. ing function and the products had to be recalled, which is problematic for firestops that are concealed behind drywall in buildings. 4.5 Water treatment Pastes for caulking purposes are similarly unstable. This Water glass is used as coagulant/flocculant agent in waste too has resulted in recalls and even litigation. Only 3M's water treatment plants. Waterglass binds to colloidal “Expantrol” version, which has an external heat treatment molecules, creating larger aggregates that sink to the bot- that helps to seal the outer surface, as part of its process tom of the water column. The microscopic negatively standard, has achieved sufficient longevity to qualify for charged particles suspended in water interact with sodium DIBt approvals in the US for use in firestopping silicate. Their electrical double layer collapses due to Not unlike other intumescents, sodium silicate, both in the increase of ionic strength caused by the addition of bead form and in liquid form are inherently endothermic, 4.8 Niche and hobby uses 3

prill form. The absence in the US of mandatory aging tests, whereby PFP systems are made to undergo sys- tem performance tests after the aging and humidity ex- posures, are at the root of the continued availability, in North America, of PFP products that can become inop- erable within weeks of installation. Indiscriminate use of sodium silicates without proper waterproofing mea- sures are contributors to the problems and risk. When sodium silicates are adequately protected, they function extremely well and reliably for long periods. Evidence of this can be seen in the many DIBt approvals for plas- tic pipe firestop devices using Palusol, which use water- proofed sodium silicate sheets.

4.8.2 Food preservation

Expantrol proprietary sodium silicate suspended in an about 6.5 mm thick layer of red rubber, type 3M FS195, inserted into a metal pipe, then heated, to demonstrate hard char intumescence, strong enough to shut a melting plastic pipe.

World War I poster suggesting the use of waterglass to preserve eggs (lower right).

Sodium silicate was also used as an egg preservation agent through the early 20th century with large success. When fresh eggs are immersed in it, bacteria which cause the Palusol based intumescent plastic pipe device used for commer- eggs to spoil are kept out and water is kept in. Eggs can cial firestopping. be kept fresh using this method for up to five months. When boiling eggs preserved this way, it is well advised to pin-prick the egg to allow steam to escape because the due to liquid water in the water glass and hydrates in the shell is no longer porous.[11] 4 4 USES

4.8.3 Metal repair 4.8.5 Homebrewing

Sodium silicate flocculant properties are also used to Sodium silicate is used, along with magnesium silicate, in clarify wine and beer by precipitating colloidal parti- muffler repair and fitting paste. When dissolved in water, cles. But as a clearing agent sodium silicate (water glass) both sodium silicate and magnesium silicate form a thick is sometimes confused with isinglass which is prepared paste that is easy to apply. When the exhaust system of an from collagen extracted from the dried swim bladders of internal combustion engine heats up to its operating tem- sturgeon and other fishes. Eggs preserved in a bucket of perature, the heat drives out all of the excess water from waterglass gel, and their shells, are sometimes also used the paste. The silicate compounds that are left over have (baked and crushed) to clear wine.[14] glass-like properties, making a temporary, brittle repair.

4.8.6 Aquaculture

Sodium silicate gel is also used as a substrate for algal 4.8.4 Automotive repair growth in aquaculture hatcheries.

Sodium silicate is also used currently as an exhaust sys- 4.8.7 Safe construction tem joint and crack sealer for repairing mufflers, res- onators, tailpipes and other exhaust components, with A mixture of sodium silicate and sawdust has been used and without fiberglass reinforcing tapes. In this applica- in between the double skin of certain safes. This not only tion, the sodium silicate (60-70%) is typically mixed with makes them more fire resistant, but also makes cutting kaolin (40-30%), an aluminium silicate mineral, in order them open with an oxyacetylene torch extremely difficult to make the sodium silicate “glued” joint opaque. The due to the smoke emitted. sodium silicate, however, is the high temperature adhe- sive; the kaolin serves simply as a compatible high tem- perature coloring agent. Some of these repair compounds 4.8.8 Crystal gardens also contain glass fibres to enhance their gap-filling abili- ties and reduce brittleness. When crystals of a number of metallic salts are dropped into a solution of water glass, simple or branching Sodium silicate can be used to fill gaps within the head stalagmites of coloured metal silicates are formed. This gasket. Commonly used on aluminum alloy cylinder phenomenon has been used by manufacturers of toys and heads, which are sensitive to thermally induced surface chemistry sets to provide instructive enjoyment to many deflection, and can be caused by many things includ- generations of children from the early 20th century till ing head-bolt stretching, deficient coolant delivery, high the present. An early mention of crystals of metallic cylinder head pressure, over-heating, etc. salts forming a "chemical garden" in sodium silicate is “Liquid glass” (sodium silicate) is added to the system found in the 1946 Modern Mechanix magazine.[15] Metal through the radiator, and allowed to circulate. Sodium salts used included the sulfates and/or chlorides of cop- silicate is suspended in the coolant until it reaches the per, cobalt, iron, nickel and manganese. cylinder head. At 100–105 °C sodium silicate loses water molecules to form a glass seal with a re-melt temperature 4.8.9 Pottery above 810 °C. A sodium silicate repair will last two years, sometimes Sodium Silicate is used to create a crackle effect in pot- longer. The repair occurs rapidly, and symptoms disap- tery, usually wheel-thrown. A vase or bottle is thrown pear instantly. This repair only works when the sodium on the wheel, fairly narrow and with thick walls. Sodium silicate reaches its “conversion” temperature at 100–105 silicate is brushed on a section of the piece. After 5 min- °C. Contamination of engine oil is a serious possibil- utes, the wall of the piece is stretched outward with a rib ity in situations in which a coolant-to-oil leak is present. or hand. The result is a wrinkled or cracked look. Sodium silicate (glass particulate) contamination of lu- It is also the main agent in “magic water”, which is used bricants is detrimental to their function. when joining clay pieces, especially if the moisture level Sodium silicate solution is used to inexpensively, quickly, of the two differs.[16] and permanently disable automobile engines. Running an engine with about 2 liters of a sodium silicate solu- tion instead of motor oil causes the solution to precipi- 4.9 Sealing of leaking water containing tate, catastrophically damaging the engine’s bearings and structures pistons within a few minutes.[12] In the United States, this procedure was used to comply with requirements of the Sodium silicate with additives was injected into the Car Allowance Rebate System (CARS) program.[12][13] ground in order to harden it and thereby to prevent further 5 leakage of highly radioactive water from the Fukushima [3] Gerard Lagaly, Werner Tufar, A. Minihan, Daiichi nuclear power plant in Japan in April, 2011.[17] A. Lovell “Silicates” in Ullmann’s Encyclope- The residual heat carried by the water used for cooling the dia of Industrial Chemistry, Wiley-VCH, 2005. damaged reactors accelerated the setting of the injected doi:10.1002/14356007.a23_661 mixture. [4] See also: On June 3, 1958, the USS Nautilus, the world’s first nu- • Leopold Wolff, Das Wasserglas: Seine Darstel- clear submarine, visited Everett and Seattle. In Seattle, lung, Eigenschaften und seine mannichfache An- crewmen dressed in civilian clothing, were sent in to se- wendung in den technischen Gewerben [Water- cretly buy 140 quarts of an automotive product contain- glass: its preparation, properties, and its manifold ing sodium silicate (originally identified as Stop Leak) to uses in technical commerce] (Leipzig, (Germany): repair a leaking condenser system. The Nautilus was en Quedlinburg, 1846). route to the North Pole on a Top Secret mission to cross • Emile Kopp (1857) “Sur la préparation et les pro- the North Pole submerged.[18] priétés du verre soluble ou des silicates de potasse et de soude; analyse de tous les travaux publiés jusqu'a ce jour sur ce sujet” (On the preparation and prop- 4.9.1 Cartridges erties of water-glass or the silicates of potash and soda; analysis of all works published until today on this subject) Le Moniteur scientifique, 1 : 337-349, A historical use of the adhesive properties of sodium sili- 366-391. cates is the production of paper cartridges for black pow- • der revolvers produced by Colt’s Manufacturing Com- Hermann Krätzer, Wasserglas und Infusorienerde, deren Natur und Bedeutung für Industrie, Technik pany during the period from 1851 until 1873, especially und die Gewerbe [Water-glass and soluble earths, during the American Civil War. Sodium silicate was used their nature and significance for industry, tech- to seal combustible nitrated paper together to form a con- nology, and commerce] ( (Wien), Austria: ical paper cartridge to hold the black powder, as well as Hartleben, 1887). to cement the ball or conical bullet into the open end • Hermann Mayer, Das Wasserglas; Sein Eigen- of the paper cartridge. Such sodium silicate cemented schaften, Fabrikation und Verwendung auf Grund paper cartridges were inserted into the cylinders of re- von Erfahrungen und Mitteilungen der Firma volvers, thereby speeding the reloading of cap and ball Henkel & Cie. [Water-glass: Its properties, pro- black powder revolvers. This use largely ended with the duction, and application on the basis of experiences introduction of Colt revolvers employing -cased car- and communications of the firm of Henkel & Co.] tridges starting in 1873.[19][20] Similarly, sodium silicate (Braunschweig, Germany: Vieweg, 1925). was also used to cement the top wad into brass shotgun • Morris Schrero, Water-glass: A Bibliography (Pitts- shells, thereby eliminating any need for a crimp at the burgh, Pennsylvania: Carnegie Library, 1922). top of the brass shotgun shell to hold a shotgun shell to- [5] Johannes van Helmont, Opuscula medica inaudita, gether. Reloading brass shotgun shells was widely prac- ( (Coloniæ Agrippinæ), (Germany): Jost Kalck- ticed by self-reliant American farmers during the 1870s, hoven (Jodocum Kalcoven), 1644), part I: De Lithiasi. On using the same waterglass material that was also used to page 53, van Helmont mentions that alkalis dissolve sili- preserve eggs. The cementing of the top wad on a shotgun cates: “Porro lapides, gemmae, arenae, marmora, silices, shell consisted of applying from 3 to 5 drops of waterglass &c. adjuncto alcali, vitrificantur: sin autem plure alcali on the top wad to secure it to the brass hull. Brass hulls coquantur, resolvuntur in humido quidem: ac resoluta, for shotgun shells were superseded by paper hulls start- facili negotio acidorum spirituum, separantur ab alcali, ing around 1877. The newer paper-hulled shotgun shells pondere pristini pulveris lapidum.” (Furthermore, stone, gems, sand, marble, silica, etc., become glassy by the ad- used a roll crimp in place of a waterglass cemented joint dition of alkali: but if roasted with more alkali, they are to hold the top wad in the shell. However, whereas brass dissolved in moisture: and the former weight of the stone shotshells with top wads cemented with waterglass could powder is separated from the alkali and released by simply be reloaded nearly indefinitely (given powder, wad, and adding acid.) shot, of course), the paper hulls that replaced the brass hulls could be reloaded only a few times. [6] A number of other alchemists supposedly discovered potassium silicate before van Helmont. See: • Giambattista della Porta in his book Magia naturalis sive de miraculis rerum naturalium (1567), men- 5 References tions that cream of tartar (tartari salis) causes pow- dered quartz (crystallum) to melt at a lower temper- [1] Greenwood, Norman N.; Earnshaw, Alan (1997). Chem- ature. See: Baptista Porta, Magia naturalis sive de istry of the Elements (2nd ed.). Butterworth-Heinemann. miraculis rerum naturalium, libri iiii [Natural magic ISBN 0080379419. or on the miracles of nature, in four books] (Lyon (Lugdunum), France: Guillaume Rouillé (Guliel- [2] Wells A.F. (1984) Structural Inorganic Chemistry 5th edi- mum Rovillium), 1569), pages 290-291, “Crystal- tion Oxford Science Publications ISBN 0-19-855370-6 lus, ut fusilis fiat” (quartz, so made molten). 6 7 EXTERNAL LINKS

• There is some evidence that the alchemist Basil schnelle Verbreitung des Feuers in Theatern, als Valentine prepared potassium silicate in 1520. See: Bindemittel, firnißartigen Anstrichen u.s.w.” (On Kohn, C. (1862) “Die Erfindung des Wasserglas im a new product from silica and potassium; and its Jahre 1520” (The invention of waterglass in the year useful application as a protection against the rapid 1520), Zeitschrift des Oesterreichischen Ingenieur- spread of fire in theaters, as a glue, varnish, etc.) Vereins (Journal of the Austrian Engineer Associ- Polytechnisches Journal, 17 : 465-481. ation), 14 : 229-230. [9] VonWagner, Rudolf (1892 translation of 13th edition by However, subsequently an article pointed out that the sub- Willian Crookes) Manual of Chemical Technology stance prepared by in 1520, by Agricola in 1550, by van Helmont in ca. 1640, and by Glauber in [10] Burch, Paula (March 22, 2010). “Sodium silicate as a fix- 1648 was not the waterglass that Fuchs produced in 1818. ative for dyeing”. Retrieved March 22, 2010. See: [11] How To Store Fresh Eggs • Anon. (1863) “Die Erfindung des [12] Helliker, Kevin. "The Killer App for Clunkers Breathes Wasserglases im Jahre 1520,” Kunst- Fresh Life Into 'Liquid Glass’" The Wall Street Journal, 4 und Gewerbe-Blatt, 49 : 228-230. August 2009. • Reprinted in: Anon. (1863) “Die Erfindung des Wasserglases im Jahre [13] Engine Disablement Procedures for the CARS program, 1520,” Polytechnisches Journal, 168 : cars.gov 394-395. [14] SM Tritton (1956) Amateur wine making. • Reprinted in: Anon. (1863) “Die ange- bliche Erfindung des Wasserglases im [15] “Magic garden”. Mechanix Illustrated: 88. April 1946. Jahre 1520” (On the alleged invention of waterglass in the year 1520), Neues [16] http://lakesidepottery.com/HTML%20Text/Tips/ Repertorium für Pharmacie, 12 : 271- pottery-magic-mud-magic-water-paper-clay.htm 273. [17] Daily Mail Reporter. “Liquid glass successfully plugs ra- [7] Johann Rudolf Glauber, Furni Novi Philosophici [New dioactive leak at crippled Fukushima nuclear plant”, “Mail philosophical furnace] (: Johan Jansson, Online News”, April 6, 2011, accessed April 7, 2010. 1646). In the 1661 German-language edition, see Chap- [18] Commander William R. Anderson with Clay Blair Jr., ter “LXXIX. Wie durch Hülff eines reinen Sandes oder Nautilus 90 North (Cleveland and New York: The Kißlings / auß Sale Tartari ein kräfftiger Spiritus kan er- World Publishing Co., 1959), pp. 133-137; Comman- langet werden.” (How with the help of a pure sand or sil- der William R. Anderson with Clay Blair Jr., Nautilus 90 ica / a powerful solution can be gotten from cream of tar- North (New York: The New American Library, 1959), tar). Glauber’s recipe for liquor silicum (potassium sili- 89-90 cate) appears on pages 164-166. The recipe is simple: Potassium hydrogen tartrate (cream of tartar, Sale tartari, [19] Tom Kelley (August 1995). “Making and using com- Weinstein ) is heated in a furnace until it’s converted to bustible paper pistol cartridges”. potassium carbonate. The potassium carbonate is mixed with sand in a crucible and heated until the mixture melts. [20] Kirst, W.J. (1983). Self consuming paper cartridges for the The mixture is maintained in a liquid state until it ceases percussion revolver. Minneapolis, Minnesota: Northwest to bubble (due to the release of carbon dioxide from the Development Co. potassium carbonate). The mixture is allowed to cool and then pulverized to a fine powder. When the powder is exposed to moist air, it gradually forms a viscous liq- 6 Other reading uid, which Glauber called “Oleum oder Liquor Silicum, Arenæ, vel Crystallorum” (i.e., oil or solution of silica, sand or [quartz] crystal). • Ashford’s Dictionary of Industrial Chemicals, third edition, 2011, page 8369. [8] See:

• Joh. Nep. Fuchs (1825) “Ueber ein neues Pro- dukt aus Kieselerde und Kali” (On a new product 7 External links from silica and potassium), Archiv für die gesammte Naturlehre, 5 (4) : 385-412. On page 386, Fuchs • Centre Européen d'Etudes des Silicates states that he first prepared potassium silicate in 1818: “Ich erhielt es zuerst, vor ungefähr 7 Jahren, • International Chemical Safety Card 1137 …" (I first obtained it about 7 years ago, … ); since the Fuchs’ paper was published in 1825, 7 years ear- • ChemSub Online : Silicic acid, sodium salt lier would be 1818. • ChemSub Online : Sodium metasilicate • Reprinted in: Joh. Nepomuk Fuchs (1825) “Ueber ein neues Produkt aus Kieselerde und Kali; und dessen nüzliche Anwendung als Schuzmittel gegen 7

8 Text and image sources, contributors, and licenses

8.1 Text

• Sodium silicate Source: http://en.wikipedia.org/wiki/Sodium%20silicate?oldid=654760305 Contributors: Docu, Stone, Dysprosia, Bkell, Rsduhamel, Dratman, Mboverload, SoWhy, Beland, The MoUsY spell-checker, Iantresman, M1ss1ontomars2k4, Brianhe, ArnoldRein- hold, Fluzwup, Ylee, Bobo192, Kx1186, Hooperbloob, Mdd, Alansohn, Oasisbob, Keenan Pepper, Benjah-bmm27, Velella, Trlblzr, Mindmatrix, Seansheep, DePiep, Rogerd, Alcarreau, SchuminWeb, BjKa, Physchim62, DVdm, YurikBot, Janke, Zzuuzz, Bridgman, Cmglee, Groyolo, Attilios, SmackBot, Errarel, Shoy, Mikesebok, Chris the speller, Bluebot, Mortezamohammadi, Ondrej.lipar, Yaf, Nakon, Smokefoot, Polonium, Kukini, Zaphraud, 16@r, Beetstra, [email protected], Hetar, Woodshed, Thricecube, CmdrObot, Palad- inZ06, Jane023, Cydebot, Reywas92, Grahamec, Rifleman 82, Christian75, Calvero JP, Thijs!bot, Nick Number, SvenAERTS, EdJogg, Widefox, Danroa, Numberharmonics, Postlewaight, JAnDbot, Lumber Jack second account, Jim Samphorn, Engineman, LorenzoB, Tex- torus, Nodekeeper, Eugenwpg, Leyo, MrBell, Ashcraft, Bot-Schafter, Afluegel, RayPhoenix, STBotD, MartinBotIII, Reelrt, Joeinwap, VolkovBot, N00ser, Zghajos, Axiosaurus, Finnrind, AHMartin, WereSpielChequers, Cwkmail, JetLover, Chem-awb, ImageRemovalBot, Akiry, Michał Sobkowski, Snaxalotl, CrazyChemGuy, Shinkolobwe, Phthalocyanine, Plasmic Physics, AlanM1, Gnowor, Billwhittaker, Mi- marx, Addbot, Goorky, Fyrael, Datsyuk, SamatBot, Tide rolls, PV=nRT, Rojypala, Karimi cae~enwiki, Yobot, Andrzejkosz, CheMoBot, Lưu Ly, Cepheiden, KamikazeBot, Naipicnirp, AnomieBOT, Daniele Pugliesi, Galoubet, Piano non troppo, EHRice, Materialscientist, The High Fin Sperm Whale, Ultimate sickness, REACHist, Cyfraw, Eddygp, Appeltree1, Riventree, HJ Mitchell, Tretyak, I dream of horses, A8UDI, Ondřej Groborz, Miguel Escopeta, Peterjmoran7, Oktanyum, Kiranglobal, EmausBot, John of Reading, AvicBot, Marchemence, Boringbob4wk, Makecat, , Bakulan, ClueBot NG, Rycecube57, Skoot13, CaroleHenson, Crazymonkey1123, Raffinate2, Nibor22, Minsbot, BattyBot, Qadiesh, Francesca Cattaneo, Mogism, CFSO6459, Bree’s Block, Project Osprey, Epicgenius, FrB.TG, MEMobun, Suphia lee, God2528, Helen31406 and Anonymous: 175

8.2 Images

• File:"Raise_More_Poultry...on_Farms_and_Back_Yards...More_Eggs_and_Poultry_Will_save_Beef_and_Pork."_-_NARA_- _512571.tif Source: http://upload.wikimedia.org/wikipedia/commons/8/85/%22Raise_More_Poultry...on_Farms_and_Back_Yards... More_Eggs_and_Poultry_Will_save_Beef_and_Pork.%22_-_NARA_-_512571.tif License: Public domain Contributors: U.S. National Archives and Records Administration Original artist: Unknown or not provided • File:Commons-logo.svg Source: http://upload.wikimedia.org/wikipedia/en/4/4a/Commons-logo.svg License: ? Contributors: ? Original artist: ? • File:Fs195.jpg Source: http://upload.wikimedia.org/wikipedia/commons/9/98/Fs195.jpg License: CC BY-SA 3.0 Contributors: Own work Original artist: Achim Hering • File:Hazard_C.svg Source: http://upload.wikimedia.org/wikipedia/commons/8/87/Hazard_C.svg License: Public domain Contributors: ? Original artist: ? • File:Křemičitan_sodný.PNG Source: http://upload.wikimedia.org/wikipedia/commons/1/1e/K%C5%99emi%C4%8Ditan_sodn%C3% BD.PNG License: Public domain Contributors: Vlastní sbírka Original artist: Ondřej Mangl • File:Palusolmanschette.jpg Source: http://upload.wikimedia.org/wikipedia/commons/3/3f/Palusolmanschette.jpg License: CC BY-SA 3.0 Contributors: Own work Original artist: Achim Hering • File:Sodium-metasilicate-chain-from-xtal-3D-balls.png Source: http://upload.wikimedia.org/wikipedia/commons/e/e5/ Sodium-metasilicate-chain-from-xtal-3D-balls.png License: Public domain Contributors: Own work Original artist: Ben Mills • File:Sodium-metasilicate-repeating-unit-2D.png Source: http://upload.wikimedia.org/wikipedia/commons/0/08/ Sodium-metasilicate-repeating-unit-2D.png License: Public domain Contributors: Own work Original artist: Ben Mills • File:X_mark.svg Source: http://upload.wikimedia.org/wikipedia/commons/a/a2/X_mark.svg License: Public domain Contributors: Own work Original artist: User:Gmaxwell • File:Yes_check.svg Source: http://upload.wikimedia.org/wikipedia/en/f/fb/Yes_check.svg License: PD Contributors: ? Original artist: ?

8.3 Content license

• Creative Commons Attribution-Share Alike 3.0