From Atoms to Materials

22. The box below shows some physical properties of metals and alloys. malleability ductility weight corrosion resistance melting point electrical conductivity Which property is most important for (a) stainless steel used to make basins in bathrooms? (b) titanium used to make eyeglass frames? (c) an alloy containing bismuth, tin and lead used to make fuses in electric plugs? soleplate 熨板 23. We have studied the following processes. Are they physical changes or chemical changes? Write the letters in the appropriate boxes. A. A magnet attracts iron powder from a mixture of iron and sulphur. B. Water is broken down into hydrogen and oxygen. C. An alloy is made by mixing two metals. D. A starting material is polymerized to become a plastic. E. Used aluminium cans are melted for recycling. Physical changes Chemical changes 116 Chapter Exercise © United Prime Educational Publishing (HK) Limited 2024 All rights reserved; no part of this publication may be reproduced, photocopied, recorded or otherwise, without the prior written permission of the Publisher. Sample