Topic: Matter & Energy Aim: What are some physical and chemical properties of matter? Do Now: A compound differs from a mixture in that a compound always has a (1)homogeneous composition (2)maximum of two components (3)minimum of three components (4)heterogeneous composition HW:

Physical Properties Can be recognized without changing the substance to anything else Examples: color, hardness, phase, solubility, odor, density, boiling point, melting point, conductivity

Chemical Properties Describe how a substance reacts to form new substances Examples: flammability, reactivity with H2O, reactivity with acids

Phases of Matter

Phases of Matter

Disorder, all directions, far apart, HIGHEST ENTROPY Solids, Liquids, & Gases Phase Shape Volume Particle Arrangement Solid Definite Regular, geometric patterns, vibrate, do not move, LOW ENTROPY Liquid Shape of container Loosely connected, flow, move while touching, HIGHER ENTROPY Gas Fills container Disorder, all directions, far apart, HIGHEST ENTROPY

Sample Question Under the same conditions of temperature and pressure, a liquid differs from a gas because the particles of the liquid are in constant straight-line motion take the shape of the container they occupy have no regular arrangement have stronger forces of attraction between them

Phases of Elements on the Periodic Table at STP – MUST KNOW. MUST. KNOW. Liquids: Hg, Br Gases: H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn Mark these on your Reference Table! The rest of the elements are solid at STP Which of the following elements has atoms arranged in a regular geometric pattern? Cl Hg Ag F (What is this question really asking?)

Physical vs. Chemical Property Blue color Density Flammability Solubility Reacts with acid to form H2 Sour taste Melting point Reacts with H2O to form a gas Reacts with a base to form H2O Hardness Boiling point Can neutralize a base Luster Odor

Physical vs. Chemical Property Blue color - P Density - P Flammability - C Solubility - P Reacts with acid to form H2 - C Sour taste – P Melting point – P Odor – P Reacts with H2O to form a gas - C Reacts with a base to form H2O - C Hardness - P Boiling point - P Can neutralize a base - C Luster - P

Physical & Chemical Changes Physical Change change in appearance Size, shape, phase NO NEW SUBSTANCE IS PRODUCED (think – phase, physical)

Physical & Chemical Changes NEW SUBSTANCE PRODUCED Different properties Chemical changes cannot be undone

Evidence of a Chemical Change Production of a gas (2 ways to know) Formation of a precipitate Color change Release or absorption of energy Temperature change Endothermic – reactants + energy  product Container gets cold Exothermic – reactants  product + energy Container gets hot Giving off light

Examples Physical Changes Chemical Changes Aluminum foil is cut in half. Milk goes sour. Clay is molded into a new shape. Jewelry tarnishes. Butter melts on warm toast. Bread becomes toast. Water evaporates from the surface of the ocean. Rust forms on a nail left outside. A juice box in the freezer freezes. Gasoline is ignited. Rubbing alcohol evaporates on your hand. Hydrogen peroxide bubbles in a cut.   A match is lit. Your body digests food. You fry an egg.

Physical vs. Chemical Change Sodium hydroxide dissolves in H2O Hydrochloric acid reacts with potassium hydroxide to produce a salt, water, & heat A pellet of sodium is sliced in two H2O is heated and changed to steam Potassium chlorate decomposes to potassium chloride & oxygen gas Iron rusts Evaporation Ice melting Wood rotting