Classification of Matter Ch. 15 Ms. Dice BIG IDEA: Matter exists as either a pure substance or a mixture.

Section 1: Composition of Matter The bottom of a pail holding ocean water will have sediment that has settled overtime. The water itself, however, will still be salty. Why doesn’t the salt settle with the sediment?

A. Substances Matter: anything that takes up space and has mass Everything around us is made up of matter Matter is either a pure substance or a mixture of substances Substance is a type of matter with a fixed composition. A substance can be an element or a compound Describe the types of substances present in an ice cream soda.

1. Elements An element is a substance made up of atoms that are all alike.

2. Compounds Two or more elements can combine to form substances called compounds. A compound is a substance in which the atoms of two or more elements are chemically combined in a fixed proportion. (example: water) The elements that make up a compound cannot be separated by physical means. Compare: How are elements and compounds related?

B. Mixtures A mixture is matter composed of two of more substances that can be separated by physical means. Two Types: Heterogeneous mixture Homogeneous mixture

1. Heterogeneous Mixtures A mixture in which different materials remain distinct is called a heterogeneous mixture. (example: salad dressing, salad) Some components are easy to see Some components you cannot see with the bare eye

Types of Heterogeneous Mixtures 1. A suspension is a heterogeneous mixture made of a liquid and solid particles that settle. 2. A colloid is a heterogeneous mixture with particles that never settle.

Identifying a Colloid Tyndall Effect: Scattering of a light beam as it passes through a colloid This happens because the particles in the colloid are big enough to scatter light, but those in a solution are not.

2. Homogeneous Mixture A homogeneous Mixture is a mixture that remains constantly and uniformly mixed and has particles that are so small that they cannot be seen with a microscope. Due to the interaction between the particles, they will never settle to the bottom of a container. A solution is the same thing as a homogeneous mixture. (Examples: Tea, Vinegar, compressed gas used by divers.)

Matter Pure Substances Mixtures Homogeneous Heterogenous Compounds Elements Ex: Oxygen, Gold, Iron Salt, baking soda, sugar Ex: Lemonade, Gasoline, Steel Ex: Dirt, Blood, Milk Fill in the Blanks on this chart using your notes!

HOMEWORK Section 1: Answer Questions 1-4 in your notes