Matter and Chemical Change notes

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Matter and Chemical Change Unit Notes

Topic 1: Exploring Matter Notes Definitions:

Chemistry- the study of the properties of matter and the changes matter undergoes.

Caustic- Capable of burning, corroding or destroying organic tissue.

Homogeneous- A mixture composed of 2 or more substances where the particles are uniformly scattered. (Mixtures that are homogeneous are also called solutions. An example of a solution is sugar water.)

Heterogeneous- A mixture composed of 2 or more substances that are visible and the particles aren’t uniformly scattered. (Mixtures that are obviously heterogeneous are called mechanical mixtures. Examples: chocolate chip cookies and veggie pizza)- pg. 96

Suspensions- A heterogeneous mixture made of large particles that are uniformly mixed but will settle if left undisturbed. Examples of suspensions include flour, charcoal and chalk mixed in with water.- pg. 97

Colloids- Heterogeneous mixtures composed of fine particles evenly distributed throughout a second substance.Examples of colloids are hair gel and clouds.-pg. 97

Emulsions-Types of colloids in which liquids are dispersed in liquids. Examples of emulsions include mayonnaise, milk, jelly and salad dressing.-pg 97

Chemistry includes facts and observations about matter, laws that summarize patterns of behaviour in matter, and theories that explain the patterns of behaviour.

The particle model of matter is a scientific model that describes the behaviour of particles. It includes the following five points:

-All matter is made up of extremely tiny particles.

Each pure substance has its own kind of particle, different from the particles of other pure substances.

Particles attract each other. (The strength of the attraction depends on the type of particle.)

Particles are always moving.

Particles at a higher temperature move faster on average than particles at a lower temperature.

Scientific models help us to visualize processes that can’t be seen directly. The first 2 points of the particle model can help visualize how particles make up substances. The other 3 points of the particle model can explain properties such as density and how matter behaves when temperature changes occur.

Matter can be further classified according to its composition as a pure substance or mixture.

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Topic 2: