September 13, 2011 Journal Questions What is a pure substance that is made of only one kind of atom? What classification of matter can be separated into two simpler parts using physical means? What type of mixture is a solution? What is a pure substance that is made up of more than one kind of element?

How is matter classified Chemistry Ms. Briones Chapter 1 section 3

Classifying matter Everything around you- water, air, plants, and your friends – is made of matter. All matter is composed of about 110 different kinds of atoms.

Atoms Atoms are so small that even the biggest atoms would take more than 3 million of them side by side to cover one millimeter.

Pure substances Every pure substance has characteristic properties that can be used to identify it. Characteristic properties can be physical or chemical properties. Example: Copper always melts at 1083°

Two types of pure substance: Elements: contain only one kind of atom. Ex: copper and bromine.

Compounds Pure substance that are not elements are compounds. Compounds are composed of more than one kind of atom. They are represented by formulas. Ex. H20

Mixtures A sample of matter that contains two or more pure substances is a mixture. Most foods are mixtures, sugar and salt are the rare exception. Look in your book on page 25 figure 18.

Homogeneous Heterogeneous Two types of mixtures Homogeneous Heterogeneous

Homogeneous Sweetened tea and 14-karat gold are examples of homogeneous mixtures. Pure substances are distributed uniformly throughout the mixture. Gasoline, syrup, and air are homogeneous mixtures.

Heterogeneous Example: substances do not evenly mixed.

Classify each of the following as element, compound, or mixture and explain your reasoning. Substance A: a black and yellow powder that can be separated with a magnet Substance B: an orange solid, which upon heating in a test tube, turns black and forms a shiny liquid on the walls of the test tube Substance C: a shiny solid that melts to a shiny liquid

Difference between a compound and a mixture Compound: has two or more elements chemically joined together. Mixture: is composed of two or more substances physically mixed together but not chemically joined.

Separating mixtures You can separate glass bottles based on their color and metal cans based on their attraction to a magnet. Techniques used include: Filtration Distillation evaporation

Your turn… Pg. 28 #’s 1-8 HW: finish the questions (1-8)

Research Aluminum Research and identify at least five items that you encounter on a regular basis that are made of aluminum. (pg. 29) Research the changes that have occurred in the design and construction of aluminum soft-drink cans and the reasons for the changes. Record a list of items that help illustrate why aluminum is a good choice for this product. (pg. 29)