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Unit 1 Stoichiometry. Chemistry 2202 September 2007 Contains information written by CDLI. What is Matter?. Matter is defined as anything that takes up space and has a mass Chemicals are a simple type of matter Everything is made up of chemical, so they are always around you.
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Unit 1Stoichiometry Chemistry 2202 September 2007 Contains information written by CDLI
What is Matter? • Matter is defined as anything that takes up space and has a mass • Chemicals are a simple type of matter • Everything is made up of chemical, so they are always around you
What is Chemistry? • The study of matter, its properties, and the changes it undergoes • There are two branches: • Pure • Deals with describing known substances and discovering new compounds • Applied • The search for uses for chemical substances
Why use Chemistry? • New chemicals are discovered or produced every day. • The composition (make up) and properties of each new substance is researched and documented • It may take years to fully understand the properties of one substance
There is a close link between chemistry, technological innovation and society's needs. • Modern society places demands on science and technology to solve problems. • Many of the technologies and conveniences that you are accustomed to are the result of interaction between chemists and technologists. • Can you think of any examples? • Chemists discover new materials and their properties, and technologists use the materials and the properties to meet the needs of society.
Environmental Concerns??? • The study of chemistry also has implications for the environment - good and bad. • As members of society, you have a role in deciding whether the risks of developing and using new substances are worth the benefit derived from their use. • Example: New fuels, pesticides • Can you think of any more?
Properties of Matter • The characteristics that help you to describe matter • Examples of properties are: • Physical state • Colour • Odour • Examples of chemical properties • Reactivity with water • Reactivity with acids • See table 1.1 on page 5 for a complete list of properties
States of Matter Removing energy Adding energy
Changes in States of Matter • Melting • Change from a solid to a liquid • Freezing (or fusion) • Changing from a liquid to a solid • Vapourization • Change from a liquid to a gas • Condensation • Change from a gas to a liquid • Sublimation • Change from a gas to solid AND from a solid to a gas
Classifying Matter • Mixture • Physical combination of two or more substances • Two type: • Heterogeneous – different components are visible • Homogeneous – mixture looks like one substance • Pure substance • Has a definite composition that stays the same in response to physical changes • Element • Pure substance that cannot be broken down smaller • Compound • Pure substance formed by two or more elements • Can be broken down into simpler parts (elements or other compounds)
In-Class Assignment • Read over notes handed out last class • Complete the questions highlighted in the boxes • Questions should be completed in class to avoid homework