Preparation of Iron by Aluminothermic Process

Preparation of Iron by Aluminothermic Process. Roast iron oxide in an iron crucible (for what purpose ). Prepare a mixture of 

25 g of the iron oxide and 8 g of an aluminium powder. Place 5 g of a calcium fluoride powder, and then the reaction mixture onto the bottom of a well dried chamotte crucible (a crucible can be made from a sheet of asbestos by fastening it with a wire). Tamp the contents with a pestle and make a hollow in them with the aid of a test tube (Fig. 120). Extract the tube and lower into the formed hollow first a twisted magnesium ribbon cleaned with emery paper, and then an incendiary mixture prepared by mixing 9 g of barium perox- 

After the crucible cools, break it, extract the metal bead, and weigh it. Determine the yield in per cent. Write the equation of the reaction. 

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