Unit 1StoichiometryChemistry 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:1. Pure

Deals with describing known substances and discovering new compounds

2. 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

Adding energy

Removing 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