 Solid: maintains a fixed volume and shape  Liquid: maintains a fixed volume but takes the shape of the container  Gas: occupies the entire volume available  Plasma: occurs at high temperatures

 Physical Properties : examples: texture, shape, size, color, odor, volume, mass, weight, and density Chemical Properties :  example: color change, energy given off or absorbed, gas given off, odor change, light, solid produced from solution

Physical Change : when objects undergo a change that does not change their chemical nature. Involves a change in physical properties Chemical Change : substances are changed into different substances. The composition of the substance changes.

 Intensive Properties: Properties that do not depend on how much of the substance you have.  Examples: Temperature, pressure, density, boiling point, solubility, color  Extensive Properties: Depend on the amount of the substance.  Examples: Mass and volume

 Density= Mass/Volume  Describes the degree of compactness of a substance – ( how closely packed together the atoms of an element, molecule or compound are.)  Is a physical or intensive property.

Element:  a pure chemical substance composed of atoms with the same number of protons  not easily broken down into it’s smaller parts  very distinctive properties  properties are different from the compounds they make up Gold Mercury Sodium Chlorine Gas

COMPOUND:  has a constant composition with fixed ratios of elements  physical properties such as boiling point or melting point of pure substances constant.  Example: pure water boils at 100 °C Table salt: NaCl Pure Water: H 2 O Carbon Dioxide: CO 2

MIXTURE : a combination of two or more substances that are not chemically united do not exist in fixed proportions most natural substances are mixtures

MIXTURES:  can be physically separated into pure compounds or elements.  just about everything that you can think of is probably a mixture.  may exhibit a changing set of physical properties. Concrete Sea Water Vegetable soup

Hetero :  indicates difference  consists of visibly different substances or phases  the four phases are gas, liquid, solid, and plasma  Example: beach sand, vinegar and oil salad dressing, air with clouds Italian Salad Dressing Jello with Fruit Air with Clouds

 "Dancing Raisins" shows liquid, solid, and gas substances in a heterogeneous mixture. Vinegar + Baking Soda – forms a heterogeneous solution: there are liquids and gases present.

Homo :  indicates sameness  has the same uniform appearance and composition throughout.  are commonly referred to as solutions.  Examples: corn oil, white vinegar, sugar solution, air (with no clouds) Kool-Aid Swimming Pool Water Air with no Clouds

 Are distinguished by particle size.  Homogeneous solutions have particles which are the size of atoms or molecules - too small to be seen.  Homogeneous solutions are two or more substances in a single phase.  The concentrations may be expressed using a variety of measures.

 Fundamental principle that states that matter cannot be created or destroyed.  In a chemical reaction the sum of all the masses of the substances involved in the reaction (reactants) is equal to the sum of all of the masses of the substances produced by the reaction (products).  No matter is gained or lost.

 The mass of the part (usually in grams) divided by the mass of the whole (usually in grams) times 100.  mass % = mass of part / mass of whole X 100  Example: Hot Chocolate with Marshmallows mass of marshmallows: 2.5 grams mass of hot chocolate with marshmallows: grams   % Mass of Marshmallow:  (2.5 g / g) X (100)  = 2.38 %

 To write a symbol for an element - you must follow these rules:  1 st letter is always a capital letter.  2 nd letter (if there is one) is always lower case  Examples: Hydrogen: HMercury: Hg Chlorine: ClLead: Pb Phosphorus: PPotassium: K

 Compounds have a definite composition.  The formula is very specific for that compound.  If the formula changes in any way –it becomes a different compound.  Examples : Water: H 2 O Hydrogen Peroxide: H 2 O 2 Iron (II) Oxide: FeO Iron (III) Oxide: Fe 2 O 3 Carbon Dioxide: CO 2 Carbon Monoxide: CO