What is the process of Passivation of Stainless Steel using Hydroflouric Acid and Nitric Acid solution?
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Passivation accomplishes two things.  First, it removes any stray particles of mild steel that may be present on the surface of the stainless steel.  Second, it builds a protective layer of corrosion on the surface of the stainless steel by slightly corroding the stainless steel itself.  \n\nThis process is desirable when the steel will be subjected to harsh environments, such as submersion or heavy exposure to seawater.
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ammonium nitrate and aluminum hydroxide\n\nNH4NO3 + Al(OH)3\n\nThe aluminum hydroxide is insoluble when formed and will precipitate out of the solution as a solid powder.
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B.\n\nthe process is called passivation. and may be increased to a greater extent on purpose by electrolysing aluminum in acid to increase the oxide layer. this is called anodizing.
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1) Depends on environmental conditions\n2) Oxidation of iron--- 2Fe + 3O2---> 2Fe2O3\n3) Not easily.  To remove rust, phosphoric acid (naval jelly) is good\n4) Ultimate weapon: Cadmium plate, epoxy primer, epoxy finish coating.
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Actually the copper doesn't come directly from the solution...\n\nNot sure how much detail you want, but it does use electroplating.  This means that it uses electricity to plate metal on an object.  The stainless steel object is put on the "positive end" and a lump of pure copper is placed on the "negative end."  A low voltage is used because a high voltage plates too fast, and the layer will peel off quickly.  If copper is the plating, then the solution must be a fairly low-concentration copper sulfate (CuSO4) solution, meaning that copper is the only metal present in the electrochemical cell.  The negative end is called the anode, and this decreases in mass as its copper ions are taken to the positive end -- the cathode.  \n\nThis method of plating multiple metals is actually fairly common, because the properties of each one can be combined.  Nickel can be used for farm equipment and engines because it can withstand a lot of force, silver is used for decoration, chromium is used to withstand a lot of use (like a spoon).  Copper is able to conduct heat and helps food cook evenly.
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There are a vast number of water soluble corrosion inhibitors.\n\nAt the simple end of the scale - Sodium nitrite, sodium tolytriazole, zinc phosphate, borates, molybdates, vanadates and chromates all inhibit rust.\n\nThere are also proprietary organic compounds (some phosphate esters, ethanolamides, etc) also inhibit rust.\n\nIt all depends on whether you want the inhibition to be short lived or long lived (nothing is "permanent") and whether the inhibition is an "in use" inhibitor (like, say, a corrosion inhibitor in cooling water) or "static" (like phosphate "rust converters" used prior to painting.
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Chromium process with outstanding spreadability and covering power. High tolerance for chromium(III), works at low temperatures and chrome acid concentrations. \n\nIn chemistry, chromic acid is a hypothetical chromium (Cr) compound, yet to be isolated, that would have the formula H2CrO4.There is a related acid, also yet to be isolated called dichromic acid with the formula H2Cr2O7. While these acids are not available, they are known through their divalent anions (chromate and dichromate respectively) and the compounds formed from them. Please note that the acid anhydride of chromic acid exists, chromium(VI) oxide or chromium trioxide (CrO3), and that industrially, this compound is sometimes sold as "chromic acid". This compound is an intensely-colored dark red/orange brown, water-soluble, granular solid which is stable by itself, but is a strong oxidant which will react when mixed with many things that can be oxidized. Ethanol, for example, will ignite on contact with it.\nIn all of the compounds discussed here, the element chromium is in oxidation state +6 (or VI). Chromium(VI) is often referred to as hexavalent chromium. Although chromium can exist in a number of oxidation states, hexavalent chromium is commonly reduced in redox reactions to a +3 oxidation state, where the Cr3+ ion is a distinctively different blue green color. Hexavalent chromium compounds are toxic and carcinogenic.\n\nChromic acid solutions are generally acidified aqueous solutions of chromate or dichromate salts. These solutions tend to be powerful oxidants, capable of destroying all organics in glassware and so often used for the cleaning of glass. Such solutions are often red-brown, orange, or yellow colored depending on concentration.\n\n\n     D3 is an oil hardening, high carbon/chromium type tool steel with high wear resistance. it hardense with a very slight change in size. the alloy possesses very high compressive strength and is deep hardening.\n \nchemical composition of D3 steel in wt percentage:\n\nC - 2.05\nSi- 0.25\nMn- 0.30\nCr- 11.50
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Practical.  Is used all the time for stainless steel fabrication.  Less clean up and splatter than mig welding.
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There's two things you're being asked to recognize.\n(1) what kind of reaction is this\n(2) is it going to go forward?\n\nLets deal with them in order.\n\n(1)  What kind of reaction is it.  \n\nI find it very helpful personally to say the names of the molecules out loud.\n\nPhosphoric Acid reacts with Strontium Hydroxide to form what?\n\nWell, the first reactant is an acid, right? The second reactant is a metal hydroxide, like sodium hydroxide, so its a base.  That makes this an acid-base neutralization.  There's no redox chemistry going on here, so the bonds in the polyatomic anion, phosphate (PO4 (3-) ) are going to all remain intact.\n\nRemember, an acid + base neutralization will always form water and a salt.  In this case , your salt would be a combination of the non-hydrogen portions of the acid (PO4) and the metal.  \n\n\n(2)  Will this reaction go forward?\nStrontium hydroxide is moderately soluble in water.  The phosphate salt very nonsoluble.  That means that the product of the displacement will be taken "out" of the solution, driving the reaction towards formation of products.\n\n*********NOTE**********\nMany of your choices aren't charge-balanced molecules.  This may help you tremendously.  I think you may have a typo in your question.\n\n*********NOTE 2*********\nOnce you fixed the choice (d) your typo was taken care of.
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(NH4)2Cr2O7 -> Cr2O3 + 4*(H2O) + N2\n\n(NH4)2SO4 + 2*(NaOH) -> 2*(NH3) + 2*(H2O) + Na2SO4\n\nFe2(SO4)3 + 6*(NH3) + 6*(H2O) -> 2*(Fe(OH)3) + 3*((NH4)2SO4)
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The process of galvanizing consists of coating metals, such as iron and steel, with a thin protective layer of zinc.  The layer of zinc provides protection to the metal from corrosion.  The result of galvanizing is a corrosion resistant product to be used for  many outdoor applications, where the weather is a factor in the life expectancy of the material.  The protective layer of zinc prevents the ferrous material from coming in contact with the oxygen causing oxidation.  Oxidation is the combination of a substance with oxygen, in iron and steel the main combination result is rust. Without this contact the ferrous material does not corrode.  An example of how this works is when iron reacts with oxygen it forms iron oxide (the main component in corrosion), however if the iron is galvanized the zinc reacts with oxygen causing zinc oxide prior to reaching the iron.  There are two types of oxide caused by iron, ferric oxide and ferrous oxide.\n\nThere are several ways to galvanize steel products, such as hot dip galvanize, electroplating galvanize, mechanical coating, zinc spraying, and zinc dust painting. In hot dip galvanize there are two different processes that are used.  One is the process of continuos hot dip galvanizing which consists of a start point and a finish point.  In between these two points the material never stops going from a raw material (iron/steel) to a finished good ready to be shipped. The other is stationary hot dip galvanizing in which an individual item is dipped into a pot of molten metal and removed. \n\n\n    The following steps are taken in hot dip galvanizing in both hot dip and continuous operations; cleaning, pickling, pre fluxing, galvanizing, cooling, finishing, inspected, and throughout the process the product is rinsed and air blown.  The main difference between the two (continuos hot dip and stationary) is that the material on a continuos operation is finished when the cycle is complete versus just dipping the material in most cases is hand finished to remove excess burs, runs, and bumps that are result of no external wipe (air knife, coal, etc.).\n\n\n=)
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1.\nMn(s) + SnCl2(aq) --> MnCl2(aq) + Sn(s)\nCr(s) + 2HBr(aq) --> CrBr2(aq) + H2(g)\nCo(s) + CaBr2(aq) --> N.R\n2Al(s) + 3Ni(NO3)2(aq) --> 2Al(NO3)3(aq) + 3Ni(s)\n\n2.\nMg + 2AgNO3 --> Mg(NO3)2 + 2Ag\nmole of Ag = 3.580 / 108 = 0.033 mole\nmole of AgNO3 = 0.033 mole = 33 mmole\nmolarity of AgNO3 = 33 / 50 = 0.66 M\n\n3.\na.soluble\nb.soluble\nc.soluble\nd.insoluble\ne.soluble\nf.soluble\ng.insoluble in water, soluble in acid\nh.soluble\n\n4.\n3NaOH(aq) + Fe(ClO4)3(aq) --> Fe(OH)3(s) + 3NaClO4(aq)\n3Na+ + 3OH- + Fe3+ + 3ClO4- --> Fe(OH)3 + 3Na+ + 3ClO4-\nFe3+ + 3OH- --> Fe(OH)3\n(NH4)2SO4(aq) + Pb(NO3)2(aq) --> PbSO4(s) + 2NH4NO3(aq)\n2NH4+ + SO42- + Pb2+ + 2NO3- --> PbSO4 + 2NH4+ + 2NO3-\nPb2+ + SO42- --> PbSO4\n\nHope it helps\npeace\nvixklen
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The overall reaction that takes place during  anodization is:\n\n2Al + 3H2O ==> Al2O3 + 3H2\n\nThis is the sum of the separate reactions at each electrode. The reactions at the anode occur at the metal/oxide and oxide/ electrolyte interfaces. The ions that make up the oxide are mobile under the high field conditions. At the metal/oxide interface the inward moving oxygen anions react with the metal:\n\n2Al + 3O2- ==> Al2O3 + 6e-\n\nAt the oxide/electrolyte interface outward moving aluminum cations react with water:\n\n2Al3+ + 3H2O ==> Al2O3 + 6H+\n\n(In case of aluminum dissolution into the electrolyte during porous film formation, the anodic reaction is:\n\n2Al ==> 2Al3+ + 6e-)\n\nThe reaction at the cathode is hydrogen gas evolution:\n\n6H+ + 6e- ==> 3H2\n\nThe sealing reaction can be written as:\n\nAl2O3 + 3H2O ==> 2AlOOH*H2O \n\nchk the link.it is very informative.
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Here is a good guide\n\nhttp://dbhs.wvusd.k12.ca.us/webdocs/Stoichiometry/Limiting-Reagent.html
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hmmm! go to this site>>>\n Candidate Reagents for Dissolution of Hanford Site Tank Sludges ...File Format: PDF/Adobe Acrobat - View as HTML\nIn none of the 5 runs with these compounds was the complete dissolution of ... acidic or moderately alkaline media without perturbing the oxidation state of ...\n \n  >>>> www.pnl.gov/main/publications/ external/technical_reports/PNNL-14378.pdf
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Copper can react with nitric acid on two different ways based on the concentration of nitric acid.\n\nIf cold and dilute nitric acid is used, then the reaction yields copper(II) nitrate, nitrous oxide(N2O) and water.\n\nCu + HNO3 ----- Cu(NO3)2 + N2O + H2O\n\nIf hot and conc. nitric acid(a stronger oxidising agent) is used, the reaction yields copper(II) nitrate, nitrogen dioxide(NO2) and water.\n\nCu + HNO3 ----- Cu(NO3)2 + NO2 + H2O\n\nP.S. - Balance the equations yourself(might take some time but use the oxidation no. method)
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to prevent rust/oxidation