Materials can be grouped as solids, liquids or gases. It is possible to change a solid to a liquid by adding heat. It is possible to reverse some changes but not others.
What you will learn in this chapter:
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How the particle theory explains the properties of solids, liquids and gases and how it can be used to explain changes of state.
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The differences between physical and chemical changes.
The law of conservation of mass. zz
How is it possible to smell the perfume the person beside you is wearing?
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How do you make a rain jacket waterproof?
Why is graphene (extracted from graphite, the material used in pencils) a revolutionary material?
Can you solve this puzzle? What element do all of the following have in common?
(Hint: this element is also the nickname for the valley in California where many of the world’s technology companies are based.)