120 likes | 211 Views
Physical Properties. Characteristics of a substance that can be observed without changing the substance Examples : color, shape, mass, length, and odor. Chemical Properties. Characteristics of a substance that indicates how it will react with other substances (“the ability to…”)
E N D
Physical Properties Characteristics of a substance that can be observed without changing the substance Examples: color, shape, mass, length, and odor
Chemical Properties • Characteristics of a substance that indicates how it will react with other substances (“the ability to…”) • The original substance is changed in observing a chemical property Examples: flammability, combustibility, neutralization, and ‘reactions’
Questions: Properties P =Physical Property C =Chemical Property • The red color of an apple • The ability of iron to rust • Flammability of Gasoline • Smell of roses • Size of a pencil • Density • Acids react with bases
Physical Changes A change where the original substance still exists The substance only changes form Examples: cut, dissolved, absorbed, a phase change Click next slide to play video
Chemical Changes • A change where a new substance is produced; the atoms have been rearranged • When you can’t get the original substance back • Properties of the new substance will be different
Chemical Changes Easily identified by the term ‘reacts’ Other ‘clues’: • Release of a gas • Change in color • Release of energy (heat, light, etc.) • Formation of a precipitate
Click next slide to play video Chemical Changes
Questions: Changes P = Physical Changes; C= Chemical Changes • Cutting wood • Digestion • Baking bread • Dissolving salt in water • An apple rotting • Melting ice • Silver tarnishing
Law of Conservation of Mass • Changes in state does not change the number of molecules in the substance or mixture • 100 g of ice = 100 g of water = 100 g of water vapor
Rock Cycle Cementation of Sediment to form Sedimentary Rock 15 19 Weathering of Igneous Rock to form Sediment 16 18 Metamormphic Rock MELTING to Magma Magma COOLING to Igneous Rock 17
More Practice: Changes Identify as Chemical (C) or Physical Changes (P) • A change in state • Newspaper turning yellow • Burning a candle • Carving a turkey • Milk going sour • Antacid tablet in water • Acid rain wearing down a marble statue • Ice melting in a soda • Sugar dissolving in Iced Tea • Water turning to steam in your shower