From Atoms to Materials

118 elements are now known. We can put them in a single list, according to their atomic numbers. Scientists have observed patterns in the properties of the elements. Based on those patterns, scientists have listed the elements in different ways. These arrangements help us to study the elements systematically. Let’s see how they do so. 13.3 Listing colours systematically Warm up Atom Chemical symbol Number of protons electrons neutrons Hydrogen H 1 1 0 Helium He 2 2 2 Lithium Li 3 3 4 Beryllium Be 4 4 5 Boron B 5 5 6 Carbon C 6 6 6 Nitrogen N 7 7 7 Oxygen O 8 8 8 Fluorine F 9 9 10 Neon Ne 10 10 10 Sodium Na 11 11 12 Magnesium Mg 12 12 12 Aluminium Al 13 13 14 Silicon Si 14 14 14 Phosphorus P 15 15 16 Sulphur S 16 16 16 Chlorine Cl 17 17 18 Argon Ar 18 18 22 Potassium K 19 19 20 Calcium Ca 20 20 20 Oganesson Og 118 118 176 Can the elements be arranged in a similar way? Can this list be improved? We often see the colour charts in computer software. In a colour chart, a large number of colours are shown. Below are some examples of colour charts. What do you think about these arrangements of colours? Are they helpful when you are choosing the colours you need? The Periodic Table 13.3 © 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