From Atoms to Materials

Fig. 13.6 If you magnify an atom to the size of the Hong Kong Space Museum, the nucleus will be as small as a sesame*. Checkpoint 13.2A sesame 芝麻 Circle T for a true statement and F for a false one. 1. An atom contains a nucleus and an ‘electron cloud’. T / F 2. A proton and an electron have almost the same mass. T / F 3. A proton carries a positive electric charge. T / F 4. An electron is much greater in mass than a proton. T / F • An atom consists of protons, electrons and neutrons. • The centre of an atom is a small, dense region called the nucleus. Protons and neutrons are packed tightly together in the nucleus. • Electrons occupy space outside the nucleus. Hong Kong Space Museum sesame atom nucleus 12 © 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