10 Extracting metals Nuffield Foundation（10提取金属纳菲尔德基金会）.pdfVIP

advanced applied science: GCE A2 UNITS © The Nuffield Foundation 2008 ACTIVITY BRIEF Extracting and purifying metals The science at work In an electrolytic cell, electricity (a flow of electrons) is used to bring about a chemical reaction. These cells are of huge commercial importance. They are used for the production and purification of many metals. Though not covered in this unit, other commercially important applications include: • manufacturing chlorine and sodium hydroxide in the alkali industry • electroplating. Your brief The unit specification says you must make a presentation outlining the applications of electrochemical changes. You will have already done work on electrochemical cells for producing electrical energy. Now you need to find out about electrolytic cells. Putting this work together will enable you to produce the required presentation. You also need to carry out a practical investigation into factors that affect the efficiency of a simple laboratory experiment in which an object is copper plated. Task 1 Industrial extraction and purification of metals Complete Study Sheet: Industrial extraction and purification of metals . Find out about the processes and describe them in terms of redox reactions. Task 2 Refining copper Complete Practical Sheet: Refining copper. You will probably work in a team to complete this task. Your teacher will advise you. Extracting and purifying metals: page 1 of 22 advanced applied science: GCE A2 UNITS © The Nuffield Foundation 2008 STUDY SHEET Industrial extraction and purification of metals By completing this study sheet you will learn about electrolysis, and its use in the extraction of sodium and aluminium, and in the purification of copper. Electrolysis Ionic solids consist of negatively charged ions and positively charged ions arranged in a giant three-dimensional lattice. Complete this sentence: Anions have a _____________ charge; cations have a _____________ charge