The production of high-grade iron from hematite and magnetite using a blast furnace involves several reactions as described above. Write the balance step for each reaction. a. Main source of heat: reaction between air and coke. b. Reaction at the bottom of the furnace: carbon dioxide reacts with unburnt coke to produce carbon monoxide. c. Reaction of carbon monoxide with hematite to produce iron (II, III) oxide and carbon dioxide. d. Reaction of carbon of monoxide with magnetite to produce ferrous oxide and carbon dioxide. e. Reaction of carbon of monoxide with ferrous oxide to produce iron and carbon dioxide. f. Additional reaction: In hotter regions, coke may act as a reducing agent. Write the balanced reaction between coke and hematite to produce iron and carbon monoxide.

Give the oxidation state of the metal for each of the following oxides of [Hint: first transition series. (Hint: Oxides of formula M3O4 are examples of mixed valence compounds in which the metal ion is present in more than one oxidation state. It is possible to write these compound formulas in the equivalent format MO-M2O 3, to permit estimation of the metal’s two oxidation states.) (a) SC2O3. (b) TiO2. (C) V2O5. (d) CrO3. (e) MnO2. (f) Fe3O4. (g) CO3O4. (h) NiO. (i) CU2O

Magnesium is an active metal; it bums in the form of powder, ribbons, and filaments to provide flashes of brilliant light. Why is it possible to use magnesium in construction?

1. Match the Process name with the Process description. process description process name Bayer process Frasch process Downs process Ostwald process Chloralkali process Charles Hall Answer A. Electrolyzing brine to produce NaOH and chlorine gas. B. Molten salts are electrolytically exposed to sodium vapor to pure alkali metals. C. Making nitric acid. D. Extracting sulfur using high pressure steam and compressed air. E. Mixed Na3AlF6, with alumina, Al203 to lower the melting point. F. Bauxite ore is processed into alumina, Al203.

d. A sample of slag from a blast furnace is analyzed for SiO, by decomposing a 0.5003-g sample with HCl, leaving a residue with a mass of 0.1414 g. After treating with HF and H2SO4 and evaporating the volatile SIF4, a residue with a mass of 0.0183 g remains. Determine the %w/w SiO; in the sample. e. A 100.0 mL sample of brackish water was made ammoniacal, and the sulphide it contained was titrated with 16.47 mL of 0.02310 M A£NO3. The analytical reaction is: 2Ag* + s → Ag,S Calculate the concentration of H2S in the water in parts per million.

How many kilograms of lead must be added to 71 kg of tin to yield a Pb-Sn alloy having a composition of 71 at% Sn-29 at% Pb? mpb= _____ kg

A furnace produces 940 tons hot metal per day which contains 92% Fe, 4.4% C and the rest being Si. The ore used is hematite and pure silicon. The coke as reductant contains 98% C and 2% silica. Use the periodic table and calculate: a) Mass of ore used to indirectly produce Fe per day b) Mass of coke required per day. c) Volume of air required per hour.

Consider the formation of gibbsite from dissolved aluminum as depicted below: Al3+    +       OH- -->         Al(OH)3 (gibbsite) a) balance this reaction (if necessary) b) predict how many mg of Al(OH)3 would be formed if 3 mg of Al3+ are dissolved in 1 l of water and “unlimited” OH- is available (assume this reaction goes completely to the right; there’s no worry about equilibrium dissolved Al3+).

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- Recently, the tragic accident involving the implosion of the OceanGate Titan submersible, made of titanium and carbon fiber, was reported. Discuss the mechanical behavior of the materials used in the Titan design, the possible failures associated with these materials under service conditions, and based on the lesson, discuss the alternatives for preventing this type of failure, which accounts for approximately 90% of failures that occur in metals.