Matter and its Changes

Chemical Matter Matter is anything that occupies space and has mass. All matter can be broken down into four states

What is the 4th state? Plasma - Plasmas consist of freely moving charged particles, i.e., electrons and ions. A gas into which sufficient energy is provided to free electrons from atoms or molecules and to allow both species, ions and electrons, to coexist.

Newtonian vs. Non-Newtonian Fluids Newtonian A Newtonian fluid is any fluid that exhibits a viscosity that remains constant regardless of any external stress that is placed upon it, such as mixing or a sudden application of force. Example: water, gasoline Non-Newtonian Non-Newtonian fluids can become thicker or thinner when stress is applied. More viscous or less viscous Examples: Cream – stir and gets thicker. Honey – Will harden but stirring can “loosen” it up.

Viscosity Viscosity is a measurement of how resistant a fluid is to attempts to move through it. A fluid with a low viscosity is said to be "thin," while a high viscosity fluid is said to be "thick.“ It is easier to move through a low viscosity fluid (like water) than a high viscosity fluid (like honey).

Changes in State Matter changes from one phase to another when its temperature changes.. At low temps, molecules move slowly and stick together. At high temps, particles move fast (gain energy) and collide more frequently. Many materials can exist as solids, liquids, and gases, and can change from one phase to another Ex: ICE  WATER  STEAM

Properties of Matter Physical Properties Determined with senses. Determine w/o destroying the object Ex: Color, shape, volume, density, odor, melting point, boiling point.

Properties of Matter Chemical Properties Indicates how a substance reacts with something else. Cannot be observed w/o altering substance. Ex: Flammability Reactivity

Changes in Matter Physical Change (Left): Composition of substance is unaltered. Chemical Change (Right): A NEW substance is produced. Composition altered.

Let’s Practice Below are pictures that represent the molecules in a solid, liquid, and gas. Identify each picture.

More Practice Identify each of the following as a physical property or chemical property Water boils at 100 degrees Celsius. Diamonds are capable of cutting glass. Water can be separated by electrolysis into hydrogen and oxygen Vinegar will react with baking soda. Yeast acts on sugar to form carbon dioxide and ethanol. Aluminum has a low density Ammonia is a gas at room temperature

More Practice- Chemical or Physical Change 1. glass breaking 2. hammering wood together to build a playhouse 3. a rusting bicycle 4. melting butter for popcorn 5. separating sand from gravel 6. spoiling food 7. mixing lemonade powder into water 8. Liquid chlorine vaporizing into chlorine gas

Pure Substances Always has the same composition. Unique set of physical/chemical properties. Either elements or compounds.

Elements Fundamental Substances Cannot be broken down into other substances by chemical means. Composed of one type of atom. However, most elements are found in a combined state, compounds.

Compounds Combined elements, always present in the same proportion. Can be broken down into elements by chemical means.

Compounds Example: Electrolysis of water breaks down water into hydrogen and oxygen gas. 2H 2 O (l)  2H 2 (g) + (O 2 ) (g) Compound Elements

Mixtures Has variable composition Blend of 2 or more pure substances. Two Types. 1.Homogeneous 2.Heterogeneous

Homogeneous Mixture Same composition throughout. Appears uniform. Does not have different layers or sections.

Heterogeneous Mixture Varying composition. Has different layers or sections “Chunks”