Matter and Change

A. Basic Vocabulary 1. Matter-Anything that takes up space and has mass. 2. Weight is a measure of the pull of gravity on an object; 3. mass is the amount of matter the object contains. 4. Volume-how much space an object occupies

1. Solids-have a definite volume and definite shape; molecules vibrate in place 2.Liquids-No definite shape but definite volume; molecules move slowly taking on the shape of their container 3.Gas-no definite shape or volume; move very fast

What states of matter are represented in the photograph?

Makes up 99% of the visible universe The most common form of matter A very energetic gas in which electrons are stripped from the atoms.

Plasma can be found in the Sun and … Lightning Stars and …

Close up view of atoms and their behavior Animated images are from

a. Changing states requires a change in pressure or temperature (adding or taking away energy) b. Processes of change 1. gas to liquid 2. liquid to solid 3. Solid to gas 4. solid to liquid 5. Liquid to gas condensation freezing sublimation melting evaporation, boiling

 Materials differ in terms of the kind of matter they contain.  Matter that has a uniform and definite composition is called a substance.  Substances can be identified as either an element, compound, or a mixture.

A pure substance that cannot be broken down any further has just one type of atom Atoms are the smallest part of an element Can be one atom or a molecule (2 atoms joined) Examples might be Oxygen (O), Nitrogen (N), Carbon (C) and Hydrogen (H). These 4 are necessary to all life Symbol-represents an element

contains two or more different atoms (elements) joined together. This is a molecule and it is the smallest part of a compound a chemical reaction is needed to separate elements in a compound. Examples would be water, salt, sugar Represented by formulas: H 2 O, NaCl, C 6 H 12 O 6

3. mixture 1. A mixture contains two or more different substances that are only physically joined together, not chemically. A mixture can contain both elements and compounds. There are two kinds of mixtures. Homogeneous a. Homogeneous -equal parts; evenly mixed solutions like saltwater or koolaid. Heterogeneous -uneven mix of parts. Many settle out depending on weight. Examples might include milk, muddy water and salad dressing b. Heterogeneous -uneven mix of parts. Many settle out depending on weight. Examples might include milk, muddy water and salad dressing

D. Properties of Matter 1. Properties used to describe matter can be classified as: a. Extensive – depends on the amount of matter in the sample - Mass, volume, calories are examples b. Intensive – depends on the type of matter, not the amount present - Hardness, Density, Boiling Point

2. Types of properties are… a. Physical Properties- a property that can be observed and measured without changing the material’s composition (identity). -Examples- color, hardness, melting point, boiling point, texture, odor, size b. Chemical Properties- a property that can only be observed by changing the composition of the material. -Examples- ability to burn, decompose, ferment, react with oxygen, etc.

. 1. Physical change- A type of change that alters a material without changing it’s chemical composition. Boil, melt, cut, bend, split, crack Is boiled water still water? Is a cut piece of wood still wood? Can be reversible, or irreversible

2. Chemical change - a change where a new substance is formed that is different than the original  Examples: Burning, corroding, decomposing  Evidence of a chemical change include  Energy (light, heat or both) is absorbed or released  Endothermic-heat is absorbed cooling temperatures  Exothermic-heat is released raising temperatures and often giving off light  Color changes  Gas production (bubbling, fizzing, or odor change; smoke)