From Atoms to Materials

24. Gallium* is a metal. Some of its physical properties are listed below: Physical property Gallium Appearance at 20 °C a grey, shiny solid Melting point 29.8 °C Boiling point 2229 °C Malleability good Ductility good Electrical conductivity good (a) Which of these properties is not a typical property of metal? (b) Amy does some tests on a piece of gallium. Predict what happens when (i) she hits the gallium with a hammer. (ii) she puts the gallium in her hand for 5 minutes. 25. Plastic R is a product made from crude oil. The following flow diagram shows the key processes of making plastic R from crude oil. (a) (i) Name plastic R . (ii) State one common use of plastic R . (b) Name processes I and II . ethene other ingredients of crude oil crude oil naphtha plastic R process I process II gallium 鎵 (c) In this diagram, which material is the monomer? Which material is the polymer? 117 13 From Atoms to Materials 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