Chemistry AI Chapter 2 A. Matter ( Section 2.1) 1. Extensive property a. Mass b. Volume Property that depends on the amount of matter in an object Measure of the amount of matter an object contains Measure of the amount of space occupied by an object 2. Intensive property Property that depends on the type of matter in an object, not the amount

3. States 1. Solid-definite shape and volume; tightly packed, rigid, and orderly arranged particles; incompressible 2.Liquids- indefinite shape; definite volume; closely packed, free flowing, unorganized particles; incompressible 3.Gas- indefinite shape and volume; free flowing, unorganized particles; particles are far apart from each other; compressible

B. Classifying Matter 1. Substance (Section 2.2) a. Element Matter that has a uniform and definite composition Salt is a substance; Kool-aid is not Simplest form of matter that can exist under normal conditions (ex. Hydrogen, Oxygen) b. Compound A substance that contains two or more elements chemically combined in a fixed proportion (ex. C 12 H 22 O 11 )

b. Compound Continued Can be broken down to elements, but only by chemical means (chemical change) A Compound may have very different properties as compared to its elements NaCl – salt Na- sodium- very explosive metal Cl- chlorine- very toxic green gas

c. Symbols and Formulas 2. Mixture (Section 2.3) Used to represent elements and compounds respectively Physical blend of two or more substances Can be separated by decanting, filtration, distillation, etc.

a. Heterogeneous The composition is not uniform throughout. The mixture contains more than one phase (ex. Italian salad dressing, bag of M&M’s, oil and water) b. Homogeneous (Solution) C. Identifying Matter 1. Physical Property (Section 2.1) The composition is uniform throughout. The mixture contains only one phase. (ex. Air, stainless steel, Pepsi, tap water) A quality or condition of a substance that can be observed or measured without changing the substance’s composition (ex. color, hardness, state, melting point, smell…)

Alters a substance without changing its composition (does not change what it is made of) (ex. Change of state, cutting, tearing) Reversible or irreversible 2. Physical Changes 3. Chemical Property (Section 2.4) The ability of a substance to undergo a specific chemical change/ reaction and form a new substance 4. Chemical Change/ Chemical Reaction A change of one or more substances into other substances, this involves the rearrangement of atoms (ex. Burn, rust, ferments, explodes, corrodes, etc.)

Indication of a chemical reaction include: 1. color change 2. gas production 3. energy transfer (temperature change) 4. formation of a precipitate (solid that settles out of a liquid) 5. odor change NaHCO 3 + CH 3 COOH CO 2 + H 2 O + NaC 2 H 3 O 2 Does a physical change always mean that a chemical change has occurred?

The starting substances in a chemical reaction and they are often found on the left hand side of a chemical equation. a. Reactants The new substances that are formed in a chemical reaction and they are often found on the right hand side of a chemical equation CH 4 + 2O 2 CO 2 + 2H 2 O (Reactants) (Products) b. Products

5. Law of Conservation of Mass or Matter (Antoine Lavoisier) Mass is neither created nor destroyed during a chemical reaction; it is conserved. Atoms are only rearranged. The mass of the products is always equal to the mass of the reactants.