Summary of Textbook (p25-34, 36-39)

Hello

Today we are going to explain CH.2 of the Chemistry textbook.

From the previous posts, we explained to you that matter is everything around us.

However to understand matter fully, we must look at it on a macroscopic level.

This is like look at the sand on a beach.

If we see this sand from far away, all we see is a blob of light brown.

However, if we look closely, we can see the individual grains of sand.

In our world, matter can be in a form of a mixture, which is formed with 2 or more kinds of matter that have separate identities.

Classifying matter into either a pure form or a mixture is a big step in unders
tanding matter.

You can make a mixture by simply adding stuff to your water maybe Kool-Aid or sweetners.
Sometimes, you can find a mixture that does not scatter light and looks uniform throughout. These mixtures are called solutions.

Mixtures can be separated by using different procedures(eg. distillation).

There are few characteristics that you should know about Pure Substances:
actually you need to know this fact: the melting point and the freezing point of a pure substance is the same!!

(Info of chemical and physical changes: refer to "Changes in Matter" article)

There are few rules that you need to know (in general)

Law of Definite Composition: The compounds will have a definite composition.

Law of Multiple Proportions: The fact that two or more compounds with different proportions of the same elements.

(For summary of p36-39) refer to "All about Matter!!" article.

Thanks for tuning in.

Written by JK (Oct4,2010)

PS been edited a few times