From Atoms to Materials

Warm up helium argon methane water nitrogen oxygen carbon dioxide matter elements compounds pure substances mixtures There are many substances in air. Which of them are elements? Which of them are compounds? How do you know? Share your ideas with your classmates. 13.4 Substances present in the air We’ll now learn more about compounds and mixtures ! Air is a mixture. It contains many elements and compounds. We have just studied elements in the previous section; now we shall look at compounds and mixtures. Compounds and mixtures 13.4 © 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