Unit A:Topic 2

1. Unit A:Topic 2 Mix and Flow of Matter

2. Important Vocab • matter • particle theory matter • pure substance • mixture • http://content.blackgold.ca/ict/Divison3/mixandflow/particle.html

3. After completing this lesson you will be able to • identify the difference between a pure substance and a mixture, according to the particle theory of matter • explain the difference between a solution and a mechanical mixture • recognize that solutions are homogenous mixtures and mechanical mixtures are heterogeneous mixtures • describe solutions by using the particle theory of matter • identify common substances that are examples of pure substances, solutions, and mechanical mixtures

4. What is Matter? • All substances are made of matter. • Matter is anything that takes up space and has mass • the particle theory of matter states that all matter is made up of tiny particles. • Matter can be divided into 2 categories: • Pure substances • Mixtures

5. Pure Substances • A pure substance contains only one type of particle. • Substances don't usually occur in their pure form in nature, so in order to obtain pure substances, people must refine raw materials. • Some examples of pure substances are • gold, • aluminum, and • sugar.

7. Mixtures • Mixtures are made of two or more kinds of matter combined together (ex. stew, pop) • Mixtures can be in the form of solids, liquids, and/or gases, in any combination.

8. In each picture, there is an arrow that points to a mixture described in the list above. Write the letter that shows what kind of mixture it is. • a) a mixture of gases d) a mixture of gases in a liquid • b) a mixture of liquids e) a mixture of solids in a liquid • c) a mixture of solids f) a mixture of solids and gases

9. Are the following statements true or false?

10. Mixtures • There are two types of mixtures • Mechanical mixtures • Solutions

11. Mechanical Mixtures (Heterogenous) • Mechanical mixtures are mixtures composed of two or more substances that remain visible even after they are mixed. • Think of how granola cereal or trail mix looks • the individual ingredients such as raisins, nuts, and dried fruit remain visible even after mixing. • Concrete is another example of a mechanical mixture — the components of the sand, lime, and water used to create it often remain visible.

12. Mechanical Mixtures (Heterogenous) • Mechanical mixtures are also known as heterogeneous mixtures (uneven mixtures). • A salad dressing made of oil and vinegar is considered a heterogeneous mixture because its components — oil and vinegar — remain separate and distinct. • Think about a chocolate chip cookie. Would it be considered a mechanical mixture? Why or why not? Explain your answer.

13. Solutions (Homogenous) • Solutions are a type of mixture in which the pure substances within the solution mix together so well that they give the appearance of only one substance. • Ex. Juice, air, brass (copper and zinc), vinegar and water

14. In-between Mixtures • Hard to determine if a mixture is heterogeneous or homogenous • Suspension: a heterogeneous mixture in which the particles settle slowly after mixing • Can be filtered • Orange juice, clay mixed with water • Colloid: a heterogonous mixture in which the particles do not settle • Ex. milk • particles in a colloid can be dispersed for an even longer period of time by adding an emulsifying agent to form an emulsion • mayonnaise

16. http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/molvie1.swfhttp://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/molvie1.swf