From Atoms to Materials

13.1 Before studying atoms How can matter be classified? Matter can be classified into pure substances and mixtures (impure substances), according to its composition. A pure substance 純淨物質 mixture 混合物 matter mixtures (impure substances) pure substances hydrogen gas rubber wood paper rock iron oil In chapter 6, we learnt that matter has mass and occupies space. There are many kinds of matter. We shall study more about them now. water Matter may exist as a solid, as a liquid, or as a gas. Some can be found in nature, some are man-made. Some are hard, some are not hard. 13.1 Sorting matter Warm up A few students have thought of some criteria to classify the following matter into groups. 1. Based on the criteria they suggest, try classifying the matter into groups. 2. Do you think these classifying methods are good? Why? 3. Besides these methods, can you think of other methods to classify them? Share your ideas with your classmates. © 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