From Atoms to Materials

Snapshot abundance 蘊藏量 rare 稀有 Checkpoint 13.2C oxygen (46.6%) aluminium (8.1%) iron (5.0%) calcium (3.6%) potassium (2.6%) other elements (1.5%) silicon (27.7%) sodium (2.8%) magnesium (2.1%) Abundance* of elements in the Earth’s crust In nature, some elements are abundant, while some are rare*. The pie chart on the right shows the most abundant elements in the Earth’s crust (percentage by mass). What are the most abundant (a) metal, (b) non-metal and (c) semi-metal? 1. Read the descriptions of the elements below. Decide whether each element is a metal, a non-metal or a semi-metal. Explain your answers. Element x y z Description • melts at 114 °C •  does not conduct electricity • a shiny solid • melts at 660 °C •  conducts electricity very well • brittle • can conduct electricity (a) Element (i) is likely to be a metal because (ii) . (b) Element (i) is likely to be a non-metal because (ii) . (c) Element (i) is likely to be a semi-metal because (ii) . 2. Consider the list of elements below. iron silicon oxygen sulphur calcium boron (a) Which elements are metals? (b) Which elements are non-metals? (c) Which elements are semi-metals? 24 © 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