3 Using Magnesium to extract Titanium

Using Magnesium to Extract titanium Titanium is a very useful metal because it is abundant, has a low density and is corrosion resistant – it is used for making strong, light alloys for use in aircraft for example. Titanium cannot be extracted with carbon because titanium carbide (TiC) it is formed rather than titanium (similar reactions take place for vanadium, tungsten and molybdenum). Titanium cannot be extracted by electrolysis because it has to be very pure. Titanium is extracted by reaction with a more reactive metal (e.g. Mg, Na). Steps in extracting Titanium 1. TiO2 (solid) is converted to TiCl4 (liquid) at 900C: 2. The TiCl4 is purified by fractional distillation in an Ar atmosphere. 3. The Ti is extracted by Mg in an Ar atmosphere at 500C TiO2 + 2 Cl2 + 2 C  TiCl4 + 2 CO TiO2 is converted to TiCl4 as it can be purified by fractional distillation, TiCl4 being molecular (liquid at room temperature) rather than ionic like TiO2 (solid at room temperature). Titanium is expensive because 1. The expensive cost of the Mg 2. This is a batch process which makes it expensive because the process is slower (having to fill up and empty reactors takes time) and requires more labour and the energy is lost when the reactor is cooled down after stopping 3. The process is also expensive due to the Ar, and the need to remove moisture (as TiCl4 is susceptible to hydrolysis). 4. High temperatures required in both steps This all makes titanium expensive even though it is a relatively abundant metal. It is only therefore used to a limited amount even though it has useful properties
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Oxford Textbook Pages : 156

CGP Revision Guide Pages : 98

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Question 1 / 5

AQA Jan 2010 Paper 2 Q4 areas outside the box will not be scanned for marking group metals and their compounds are used commercially in a variety of processes and applications a state a use of magnesium hydroxide in medicine mark b calcium carbonate is an insoluble solid that can be used in a reaction to lower the acidity of the water in a lake explain why the rate of this reaction decreases when the temperature of the water in the lake falls marks extra space c strontium metal is used in the manufacture of alloys c i explain why strontium has a higher melting point than barium marks extra space wmp jan chem c ii write an equation for the reaction of strontium with water areas outside the box will not be scanned for marking mark d magnesium can be used in the extraction of titanium d i write an equation for the reaction of magnesium with titanium iv chloride mark d ii the excess of magnesium used in this extraction can be removed by reacting it with dilute sulfuric acid to form magnesium sulfate use your knowledge of group sulfates to explain why the magnesium sulfate formed is easy to separate from the titanium mark turn over for the next question turn over wmp jan chem
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Question 2 / 5

AQA Jun 2010 Paper 2 Q5 do not write outside the box sulfuric acid is an important chemical in many industrial and laboratory reactions consider the following three reactions involving sulfuric acid reaction reaction mg oh h so mgso h o the reaction of solid sodium bromide with concentrated sulfuric acid reaction h c ch conc h so h o ch ch oh a give a use for magnesium hydroxide in medicine mark b sulfuric acid behaves as an oxidising agent in reaction b i in terms of electrons state the meaning of the term oxidising agent mark b ii give the formula of the oxidation product that is formed from sodium bromide in reaction mark b iii deduce the half equation for the reduction of h so to so in reaction mark wmp jun chem do not write outside the box c the formation of ethanol in reaction uses concentrated sulfuric acid and proceeds in two stages according to the following equations stage stage h c ch h so ch ch oso oh ch ch oso oh h o ch ch oh h so c i state the overall role of sulfuric acid in reaction mark c ii outline a mechanism for stage of this reaction c iii state the class of alcohols to which ethanol belongs mark c iv draw the displayed formula of the carboxylic acid formed when ethanol is oxidised by an excess of acidified potassium dichromate vi solution marks mark turn over wmp jun chem
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Question 3 / 5

AQA Jun 2012 Paper 2 Q4 do not write outside the box metals can be extracted by different methods a give one reason why titanium cannot be extracted directly from titanium iv oxide using carbon mark b titanium steel is an alloy of titanium and iron titanium steel is extracted from the mineral ilmenite fetio in a two stage process purified fetio is first converted into a mixture of two metal chlorides these two metal chlorides are then reduced simultaneously using sodium b i write an equation for the reaction of fetio with chlorine and carbon to produce iron iii chloride fecl titanium iv chloride and carbon monoxide mark b ii write an equation for the simultaneous reduction of the mixture of iron iii chloride and titanium iv chloride to iron and titanium using sodium mark wmp jun chem do not write outside the box c scrap iron is used to extract copper from dilute aqueous solutions containing copper ii ions explain in terms of redox what happens to the copper ii ions in this extraction marks d aluminium is an expensive metal because it is extracted from molten aluminium oxide using electrolysis write the half equation for the reaction that occurs at the positive electrode during this extraction mark turn over for the next question turn over wmp jun chem
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Question 4 / 5

AQA Jun 2013 Paper 2 Q11 do not write outside the box a group metals and their compounds are used commercially in a variety of processes strontium is extracted from strontium oxide sro by heating a mixture of powdered strontium oxide and powdered aluminium consider these standard enthalpies of formation hf kj mol sro s al o s sro s al s sr s al o s use these data and the equation to calculate the standard enthalpy change for this extraction of strontium the use of powdered strontium oxide and powdered aluminium increases the surface area of the reactants suggest one reason why this increases the reaction rate suggest one major reason why this method of extracting strontium is expensive marks question continues on the next page turn over wmp jun chem b explain why calcium has a higher melting point than strontium do not write outside the box marks c magnesium is used in fireworks it reacts rapidly with oxygen burning with a bright white light magnesium reacts slowly with cold water write an equation for the reaction of magnesium with oxygen write an equation for the reaction of magnesium with cold water give a medical use for the magnesium compound formed in the reaction of magnesium with cold water marks end of questions copyright aqa and its licensors all rights reserved wmp jun chem
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Question 5 / 5

AQA Jun 2016 Paper 2 Q7 do not write outside the box a the ores used for the extraction of many metals contain metal sulfides or metal oxides various methods are used to extract metals from these ores sulfide ores such as zinc blende zns are crushed and then roasted in a stream of air to convert them into the metal oxide a i write an equation for the reaction that takes place when zns is roasted in air mark a ii state a useful substance that can be manufactured from the gaseous product of this reaction mark b zinc oxide is reduced by carbon monoxide in the extraction of zinc the carbon monoxide is produced by the incomplete combustion of methane b i write an equation for the production of carbon monoxide by the incomplete combustion of methane mark b ii write an equation for the reaction between zinc oxide and carbon monoxide mark c most copper is produced by reduction of copper ii oxide with carbon the copper ii oxide is produced by roasting chalcopyrite cufes in air copper can also be obtained from other low grade ores when these low grade ores are processed aqueous solutions containing low concentrations of cu ions are produced scrap iron is used to recover copper from these solutions c i give the ionic equation for the reaction involved in the recovery of solid copper from an aqueous solution using scrap iron include state symbols mark turn over wmp jun chem do not write outside the box c ii suggest two environmental reasons and one economic reason why the extraction of copper from solutions containing cu ions using iron is preferable to the reduction of copper ii oxide made by roasting chalcopyrite marks environmental reason environmental reason economic reason d titanium can be extracted from its ore rutile tio in a two step process using carbon chlorine and magnesium extraction of titanium is not possible by direct reduction of tio with carbon d i give equations for the two step process using carbon chlorine and magnesium marks step step d ii state why direct reduction of tio with carbon cannot be used mark wmp jun chem do not write outside the box turn over for the next question do not write on this page answer in the spaces provided turn over wmp jun chem
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