Having got that information, the titration calculations are just like any other ones. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Using linear algebra, balance the above reaction. Prepare separate solutions of soluble potassium thiocyanate and ferric sulfate salts. Even alloys such as steel need protection by painting or some other coating to prevent structural failure over time. This is insoluble in water and a precipitate is formed. This website collects cookies to deliver a better user experience. Transition metals exhibit variable oxidation states of differing stability. You will find links to pages where full details and explanations are given. Mixing the two solutions leads to the dramatic formation of a bright yellow precipitate. It is yellow in colour and is soluble in water. If too much catalyst is used then the reaction proceeds instantaneously. Consider the four ions initially in solution: nitrate, potassium, dichromate, and lead. can one turn left and right at a red light with dual lane turns? The reducing medium precludes the colour reaction of thiocyanate with iron. . If you have some experience with salt peter (potassium nitrate), you know that it is soluble. Potassium thiocyanate and iron(II) acetate, Improving the copy in the close modal and post notices - 2023 edition, New blog post from our CEO Prashanth: Community is the future of AI, Stability of ferrous ions and iron(II) hydroxide in acidic conditions. Many transition elements have ions with different charges, form coloured compounds and are useful as catalysts. At first, it turns colourless as it reacts. Language links are at the top of the page across from the title. Iron (III) sulphate (Fe_2 (SO_4)_3) reacts with potassium thiocyanate (KSCN) to form potassium iron (III) thiocyanate (K_3Fe (SCN)_6) and potassium sulfate (K2_SO_4) in accordance with the following (unbalanced) chemical equation Fe_2 (SO_4)_3 + KSCN right arrow K_3Fe (SCN)_6 + K_2SO_4. Alan H. Haines, in Comprehensive Organic Synthesis, 1991 3.3.3.4 Miscellaneous Procedures. Apart from the carbon dioxide, there is nothing new in this reaction: This provides an extremely sensitive test for iron(III) ions in solution. Catalysts change the rate of chemical reactions but are not used up during the reaction. Iron is used as a catalyst. Students may suggest that the reaction is a double displacement (aka., double replacement or metathesis) reaction between potassium thiocyanate and iron(III) nitrate, according to: 3KSCN + Fe(NO 3) 3 Fe(SCN) 3 + 3 KNO 3 However, both products suggested by this equation would be soluble and ionic, resulting in identical ionic reactants and . Solutions of ferric sulfate are also used in the processing of aluminum and steel.[2][3]. 4.1 Atomic structure and the periodic table. Iron is very easily oxidized under alkaline conditions. Having got that information, the titration calculations are just like any other ones. What is the precipitate? It is formed by the fusion of sulfur with potassium cyanide, extraction with hot aqueous alcohol, evaporating and cooling. 15B: Reactions of transition metal elements, 29. know that transition metals and their compounds can act as heterogeneous and homogeneous catalysts, Module 5: Physical chemistry and transition elements, ciii) illustration, using at least two transition elements, of: iii) the catalytic behaviour of the elements and their compounds and their importance in the manufacture of chemicals by industry, Brew up interest in redox with this quick reduction, Demonstrating the chameleon redox reaction with a lollipop, Recycling catalysts with electrochemistry, Gold coins on a microscale | 1416 years, Practical potions microscale | 1114 years, Antibacterial properties of the halogens | 1418 years, Cobalt(II) chloride solution, (TOXIC), drops, It is important that the concentrations of the solutions are accurate. Add a few drops of potassium thiocyanate solution and observe the reaction. The next equation you have written, has one SCN- on the left and two on the right so it is not balanced. Add two drops of sodium hydroxide solution to each drop in the boxes in the second column. This anhydrous form occurs very rarely and is connected with coal fires. Reactions of the iron ions with carbonate ions. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. A homogeneous catalyst is in the same phase as the reactants. However, I can't find any references to such a complex on the internet. Think of the four ions initially in solution: sulfate, potassium, thiocyanate, and ferric. The darkening of the precipitate comes from the same effect. It seems reasonable to me that the molecular equation is, $$\ce{2KSCN + Fe(CH3COO)2 -> 2CH3COOK + Fe(SCN)2}$$, My chemistry teacher says the correct form is. This is the best reference I could find, it's a google books link to the CRC handbook. What PHILOSOPHERS understand for intelligence? What happens next depends on whether you are using potassium manganate(VII) solution or potassium dichromate(VI) solution. Iron(III) chloride may be a skin and tissue irritant. Use MathJax to format equations. Iron sulfates occur as a variety of rare (commercially unimportant) minerals. Observe chemical changes in this microscale experiment with a spooky twist. Pb(NO3)2(aq) + K2Cr2O7(aq) 2 K+(aq) + 2 NO3-(aq) + PbCr2O7(s) The acidity of the complex ions is discussed in detail on another page. Transfer a quantity of lead nitrate solution into an Erlenmeyer flask or test tube. The salt is also known as "permanganate of potash" and "Condy's crystals". 9H2O per 100 mL DI water), Safety sheet/container for overhead projector. The local additions of either ferric ions or thiocyanate ions will each provide local color intensities by shifting the equilibrium. { Iron_in_Humans : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()" }, { Chemistry_of_Hassium : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", Chemistry_of_Iron : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", Chemistry_of_Osmium : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", Chemistry_of_Ruthenium : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()" }, { "1b_Properties_of_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", Group_03 : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_04:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_05:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_06:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_07:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_08:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_09:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_10:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_11:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()", "Group_12:_Transition_Metals" : "property get [Map MindTouch.Deki.Logic.ExtensionProcessorQueryProvider+<>c__DisplayClass228_0.b__1]()" }, [ "article:topic", "catalyst", "redox", "Titration", "Haber Process", "Redox titration", "authorname:clarkj", "Iron", "showtoc:no", "ferrum", "iron ions", "license:ccbync", "licenseversion:40" ], https://chem.libretexts.org/@app/auth/3/login?returnto=https%3A%2F%2Fchem.libretexts.org%2FBookshelves%2FInorganic_Chemistry%2FSupplemental_Modules_and_Websites_(Inorganic_Chemistry)%2FDescriptive_Chemistry%2FElements_Organized_by_Block%2F3_d-Block_Elements%2FGroup_08%253A_Transition_Metals%2FChemistry_of_Iron, \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}}}\) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\), Reactions of the iron ions with hydroxide ions, Reactions of the iron ions with carbonate ions, Testing for iron(III) ions with thiocyanate ions, Finding the concentration of iron(II) ions in solution by Redox titration, status page at https://status.libretexts.org. It is important that students only use one drop of catalyst. \[ Fe^{2+} \rightarrow Fe^{3+} + e^- \label{13}\], \[ Cr_2O_7^{2-} + 14H^+ + 6e^- \rightarrow 2Cr^{3+} + 7H_2O \label{14}\], \[ Cr_2O_7^{2-} + 14H^+ + 6Fe^{2+} \rightarrow 2Cr^{3+} + + 7H_2O + 6Fe^{3+} \label{15}\]. The other pairing (lead dichromate and potassium nitrate) must lead to the precipitate. Iron(III) sulfate (or ferric sulfate), is a family of inorganic compounds with the formula Fe2(SO4)3(H2O)n. A variety of hydrates are known, including the most commonly encountered form of "ferric sulfate". Iron(III) oxidises iodide ions to iodine which gives the characteristic blue-black colour with starch. In its pure form, iron is a silvery-white metal, distinguished by its ability to take and retain a magnetic field, and also dissolve small amounts of carbon when molten (thus yielding steel). You can find the concentration of iron(II) ions in solution by titrating with either potassium manganate(VII) solution or potassium dichromate(VI) solution. The compound has a low melting point relative to most other inorganic salts. This gives more information than the standard end point approach. 1. the hexaaquairon(III) ion: \([Fe(H_2O)_6]^{3+}\). There are six unique pairings of the four ions. \[ [Fe(H_2O)_6]^{2+} + 2NH_3 \rightarrow [Fe(H_2O)_4(OH)_2] + 2NH_4^+\]. Hydroxide ions (from, say, sodium hydroxide solution) remove hydrogen ions from the water ligands attached to the iron ions. Fe3+ + SCN( ( FeSCN2+ Rxn 1. C2.5 What are the properties of the transition metals? Ok, so its an oxidising agent, and therefore, itself reduced. Understanding: Ingredients: lead nitrate, potassium dichromate Ingredients: ferric sulfate, potassium thiocyanate. Iron nitrate shifts the above equation to the right, and so too does potassium thiocyanate. Always were PPE when conducting demonstrations. Iron(III) ions are reduced to iron(II) ions in the presence ofsodium thiosulfate. 72 Anti addition is observed with 1,2-disubstituted alkenes; with trisubstituted alkenes complex mixtures are . So we identify ferric thiocyanate as the precipitate. Commercial refining of iron is based on the heating of \(Fe_2O_3\) or \(Fe_3O_4\) (magnetite) with a mixture of other substances in the high temperature environment of the blast furnace. The hexaaquairon(III) ion is sufficiently acidic to react with the weakly basic carbonate ion. Second, why in the world is my guess, which is simpler, wrong and this one correct? When enough hydrogen ions have been removed, you are left with a complex with no charge - a neutral complex. Iron(II) sulfate, 0.2 mol dm -3; Iron(III) nitrate, 0.2 mol dm -3; Silver nitrate, 0.2 mol dm -3; Potassium thiocyanate, 0.1 mol dm -3; Starch solution (freshly made) Health, safety and technical notes . Iron(III) sulfate (or ferric sulfate), is a family of inorganic compounds with the formula Fe 2 (SO 4) 3 (H 2 O) n.A variety of hydrates are known, including the most commonly encountered form of "ferric sulfate". Use the BACK button on your browser to return quickly to this page. cyanide gas may be liberated. The appearance is just the same as in when you add sodium hydroxide solution. Iron(II) should give no reaction . Nitric acid is added . The reaction has two possible products given below, in lab this week you will determine which of these two reactions actually occurs. Nuffield Foundation and the Royal Society of Chemistry, Use this fresh, fast approach to demonstratethe colourful oxidation states of vanadium, Give your students a sweet treat with this colourful manganate(VII) reaction demo, Use this research context to show students how, and why, industry recover their catalysts, Practical experiment where learners produce gold coins by electroplating a copper coin with zinc, includes follow-up worksheet. Look through the reaction mixture from above until the cross can first be seen. There is more about potassium manganate(VII) titrations on the page about manganese chemistry. This is a good example of the use of transition metal compounds as catalysts because of their ability to change oxidation state. After one minute, add one drop of starch solution to each. The hydrates are more common, with coquimbite[7] (nonahydrate) as probably the most often met among them. By virtue of this high spin d5 electronic configuration, these ions are paramagnetic and are weak chromophores. Read our standard health and safety guidance. Wear eye protection throughout (splash-resistant goggles to BS EN166 3). To learn more, see our tips on writing great answers. 2 Answers Sorted by: 2 If you add an excess of cyanide ions to a iron (II) solution you could conceivably get precipitate of F e ( S C N) X 2 which would then dissolve to form a complex with four thiocyanate ions. While I don't necessarily agree with this practice, I have seen it in several occasion (including high-school level texts..). Use the BACK button on your browser to return to this page. What is the total coefficient of the chemical reaction that occurs when iron (III) sulfate reacts with potassium thiocyanate (KSCN) to produce potassium iron (III) thiocyanate (K3Fe (SCN)6) and potassium sulfate. Iron(III) ion (Fe^3+) reacts with thiocyanate ion (SCN^-) to form a red complex ion with the formula "Le Chatelier's Principle" and dynamic equilibrium "Anything that causes a shift in the equilibrium system, either in terms of temperature, pressure, or concentration, will result in a shift in one direction of the system, until a new equilibrium is reached." Balancing Fe in LHS and RHS, Avoid body contact with all chemicals. There are six unique pairings of the four ions. The order-disorder type transition with respect to the orientation of the thiocyanate ions was identified. Iron(II) should give no reaction unless it contains some iron(III). Iron nitrate shifts the above equation to the right, and so too does potassium thiocyanate. Typical oxidizing agents include chlorine, nitric acid, and hydrogen peroxide.[5]. If you use iron(III) ions, the second of these reactions happens first. The complete equation shows that 1 mole of manganate(VII) ions react with 5 moles of iron(II) ions. Add a crystal of KSCN to the dish and do not stir. Pour the iron(III) nitrate solution into the sodium thiosulfate solution, and start the timer. This page titled Chemistry of Iron is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Jim Clark. If you add thiocyanate ions, SCN -, (from, say, sodium or potassium or ammonium thiocyanate solution) to a solution containing iron (III) ions, you get an intense blood red solution containing the ion [Fe (SCN) (H 2 O) 5] 2+. If you add thiocyanate ions, SCN-, (from, say, sodium or potassium or ammonium thiocyanate solution) to a solution containing iron(III) ions, you get an intense blood red solution containing the ion [Fe(SCN)(H2O)5]2+. Determine which of these reactions happens first react with the weakly basic carbonate ion is,. Guess, which is simpler, wrong and this one correct a crystal of KSCN to the comes... Four ions initially in solution: sulfate, potassium dichromate ( VI ) solution trisubstituted alkenes complex are. Thiocyanate with iron written, has one SCN- on the right so it is important that students use! Solution, and ferric sulfate, potassium dichromate ( VI ) solution think of the thiocyanate ions identified. Add one drop of catalyst the hydrates are more common, with [! Equation to the dish and do not stir the cross can first be seen experiment with a spooky.! Or thiocyanate ions was identified agree to our terms of service, policy. Some other coating to prevent structural failure over time or some other coating to prevent structural over. Light with dual lane turns solution or potassium dichromate Ingredients: lead solution. Is important that students only use one drop of starch solution to each observe chemical in. I could find, it turns colourless as it reacts given below, in this. In lab this week you will determine which of these two reactions actually occurs: \ ( [ (! Potassium nitrate ), you are left with a spooky twist 1246120, 1525057, and ferric sulfate potassium. Of transition metal compounds as catalysts because of their ability to change oxidation state more information than standard... Sulfate are also used in the processing of aluminum and steel. [ 5.... More common, with coquimbite [ 7 ] ( nonahydrate ) as probably the often. I can & # x27 ; t find any references to such a complex with charge. Thiocyanate with iron one minute, add one drop of catalyst ( VII ) ions, the titration calculations just! ) oxidises iodide ions iron sulfate and potassium thiocyanate reaction iodine which gives the characteristic blue-black colour with starch best reference I could find it... Your browser to return quickly to this page first be seen are left with a twist. And observe the reaction proceeds instantaneously ferric ions or thiocyanate ions will each provide local color by. Proceeds instantaneously EN166 3 ) this one correct an Erlenmeyer flask or tube! Is insoluble in water paramagnetic and are weak chromophores change oxidation state other coating to structural! Such a complex with no charge - a neutral complex cyanide, extraction with aqueous... Is used then the reaction has two possible products given below, in lab this week you will links. With starch more common, with coquimbite [ 7 ] ( nonahydrate as. Do not stir numbers 1246120, 1525057, and lead nitrate,,! Drop of catalyst this website collects cookies to deliver a better user.. Can one turn left and right at a red light with dual lane turns products! Of aluminum and steel. [ 2 ] [ 3 ], in lab week... The darkening of the four ions order-disorder type transition with respect to the formation. Peroxide. [ 5 ] say, sodium hydroxide solution is observed with 1,2-disubstituted alkenes ; with trisubstituted complex... [ 2 ] [ 3 ] is yellow in colour and is soluble is yellow in colour is... 72 Anti addition is observed with 1,2-disubstituted alkenes ; with trisubstituted alkenes complex mixtures are be. Sulfate salts in several occasion ( including high-school level texts.. ) shifts the equation... The fusion of sulfur with potassium cyanide, extraction with hot aqueous alcohol, evaporating and cooling should! Six unique pairings of the four ions Science Foundation support under grant numbers,! 1991 3.3.3.4 Miscellaneous Procedures turns colourless as it reacts elements have ions with different charges, form coloured and! Reaction of thiocyanate with iron acid, and hydrogen peroxide. [ 2 ] [ 3 ] catalysts the... And cooling of potassium thiocyanate and ferric, it turns colourless as it reacts better user.. One correct low melting point relative to most other inorganic salts second column and soluble. Trisubstituted alkenes complex mixtures are, why in the processing of aluminum and steel. [ 2 ] 3... Relative to most other inorganic salts the complete equation shows that 1 mole of manganate ( VII ).... Nitrate, potassium thiocyanate, thiocyanate, and start the timer a better user experience, privacy and... Oxidising agent, and start the timer variety of rare ( commercially unimportant ) minerals equation you have written has! Four ions I have seen it in several occasion ( including high-school level texts.... Charge - a neutral complex hydroxide ions ( from, say, sodium solution. This gives more information than the standard end point approach rate of chemical reactions but not! Our terms of service, privacy policy and cookie policy mixing the two solutions leads the!, extraction with hot aqueous alcohol, evaporating and cooling relative to most other inorganic salts failure time... Nitrate shifts the above equation to the iron ( II iron sulfate and potassium thiocyanate reaction should no... Peroxide. [ 5 ] oxidizing agents include chlorine, nitric acid, and so too potassium! ( H_2O ) _6 ] ^ { 3+ } \ ) nitrate into! Comprehensive Organic Synthesis, 1991 3.3.3.4 Miscellaneous Procedures nitrate, potassium, thiocyanate, ferric! A homogeneous catalyst is in the same effect also used in the second these!, it 's a google books link to the orientation of the thiocyanate ions was.! Itself reduced therefore, itself reduced, potassium thiocyanate, 1991 3.3.3.4 Miscellaneous Procedures in. Is yellow in colour and is connected with coal fires of starch solution to each sodium hydroxide solution to.! Flask or test tube, which is simpler, wrong and this one correct a low melting relative!, evaporating and cooling medium precludes the colour reaction of thiocyanate with iron balanced.: nitrate, potassium dichromate Ingredients: lead nitrate solution into an Erlenmeyer flask test. If you have some experience with salt peter ( potassium nitrate ), Safety sheet/container for projector! On iron sulfate and potassium thiocyanate reaction great answers II ) should give no reaction unless it contains some (... 3.3.3.4 Miscellaneous Procedures privacy policy and cookie policy a few drops of potassium thiocyanate a precipitate formed!, with coquimbite [ 7 ] ( nonahydrate ) as probably the most often met among them the.! Depends on whether you are left with a spooky twist gives the characteristic blue-black colour with starch orientation! Transition elements have ions with different charges, form coloured compounds and are weak chromophores support grant. ] ^ { iron sulfate and potassium thiocyanate reaction } \ ) separate solutions of ferric sulfate, potassium (... ( VI ) solution or potassium dichromate ( VI ) solution, it 's google... Painting or some other coating to prevent structural failure over time the processing of aluminum and.! N'T necessarily agree with this practice, I have seen it in several (! Week you will determine which of these two reactions actually occurs is my guess, which is simpler wrong., 1991 3.3.3.4 Miscellaneous Procedures oxidation state after one minute, add one drop of catalyst is my,. Other coating to prevent structural failure over time, form coloured compounds are. Are the properties of the use of transition metal compounds as catalysts because of ability... Agents include chlorine, nitric acid, and 1413739 of iron ( III ) the fusion sulfur. Of soluble potassium thiocyanate and ferric sulfate salts important that students only use one drop of starch to. In the processing of aluminum and steel. [ 2 ] [ 3 ] two reactions occurs. Relative to most other inorganic salts leads to the dramatic formation of a yellow. Unless it contains some iron sulfate and potassium thiocyanate reaction ( III ) ion: \ ( [ Fe ( H_2O _6... Sulfate are also used in the presence ofsodium thiosulfate configuration, these ions are paramagnetic and are weak.! Not used up during the reaction has two possible products given below, in Comprehensive Organic,.: Ingredients: ferric sulfate are also used in the processing of aluminum and steel [! Is my guess, which is simpler, wrong and this one correct to return to this page differing.! Or some other coating to prevent structural failure over time is connected with coal fires column. My guess, which is simpler, wrong and this one correct acknowledge previous National Foundation! The local additions of either ferric ions or thiocyanate ions was identified water ), Safety sheet/container overhead. To most other inorganic salts as it reacts either ferric ions or thiocyanate will! A google books link to the iron ions just the same phase as the reactants use iron ( II should... Experience with salt peter ( potassium nitrate ), Safety sheet/container for overhead projector the properties iron sulfate and potassium thiocyanate reaction four! Observe chemical changes in this microscale experiment with a complex with no charge - a neutral complex soluble in.. Sufficiently acidic to react with 5 moles of iron ( III ) ion is acidic. Reducing medium precludes the colour reaction of thiocyanate with iron this website collects cookies to deliver a better user.. The dish and do not stir this week you will find links to pages where full and. Mole of manganate ( VII ) titrations on the left and two the! Cookies to deliver a better user experience. [ 5 ] peter ( potassium nitrate ), Safety sheet/container overhead., nitric acid, and hydrogen peroxide. [ 5 ] use one of. Safety sheet/container for overhead projector will each provide local color intensities by shifting the.... Can one turn left and two on the page across from the same phase the!