Transcript Slide 1
Kinetic Theory of Matter Matter is made up of particles which are in continual random motion. SOLIDS •Particles of solids are tightly packed, vibrating about a fixed position. • Solids have a definite shape and a definite volume. LIQUID GAS Particles of liquids are tightly packed, but are far enough apart to slide over one another. Liquids have an indefinite shape and a definite volume. • Particles of gases are very energetic and moving constantly. • Gases have an indefinite shape and a indefinite volume. There is actually 4 STATES OF MATTER PLASMA Plasma is an ionized gas. Plasmas, like gases have an indefinite shape and an indefinite volume. Plasma is the most common state of matter! STATES OF MATTER SOLID LIQUID GAS Tightly packed, in a regular pattern Vibrate, but do not move from place to place Close together with no regular arrangement. Vibrate, move about, and slide past each other Will separated with no regular arrangement. Vibrate and move freely at high speeds PLASMA Has no definite volume or shape and is composed of electrical charged particles Heating and Cooling Curves and Phase Diagrams Things to know: What do all the lines represent? Where are the phase changes and what are their names? Is energy being absorbed or released? Heating Curve for Water • This is what the graph would look like if I took some ice cubes, put them in a beaker, and heated them with a Bunsen burner. • What do you notice? Heating Curve for Water • What is happening between point B and C? • What is happening between point D and E? • Is energy being absorbed or released? Heating Curve for Water EVAPORATING Gas Liquid MELTING Solid • While the water is in a particular state, the temperature can increase. • During a phase change however, the temperature remains constant. • http://www.kentchemistry.com/links/Matter/HeatingCurve.htm Cooling Curve of Water A B C Blank • What is the phase change between A and B? • What is the phase change between C and D? • Is energy being absorbed or released? D Learning Check A. Water condenses at a temperature of 1) 0°C 2) 50°C 3) 100°C B. When a gas condenses, energy is 1) released 2) absorbed C. Melting is 1) endothermic 2) exothermic Learning Check Is energy absorbed (1) or released (2) in each of the following: ____A. Ice to liquid water ____B. Water vapor to rain ____C. Boiling water Something to think about: Why do drops of liquid water form the outside a glass of iced tea when the liquid is on the inside? Solution CS3 Is energy absorbed (1) or released (2) in each of the following: _1__A. Ice to liquid water (Endothermic) _2__B. Water vapor to rain (Exothermic) _1__C. Boiling Water (Endothermic) Condensation of water in the air that cools PHASE CHANGES Description of Phase Change Solid to liquid Liquid to solid Term for Phase Change Heat Movement During Phase Change Melting Energy (Heat) is absorbed by atoms. Freezing Energy (Heat) is released by atoms. PHASE CHANGES Description of Phase Change Liquid to Gas Gas to Liquid Term for Phase Change Heat Movement During Phase Change Evaporation/ Vaporization Energy (Heat) is absorbed by atoms. Condensation Energy (Heat) is released by atoms. PHASE CHANGES Description Term for of Phase Phase Change Change Solid to Gas Gas to Solid Heat Movement During Phase Change Sublimation Energy (Heat) is absorbed by atoms. Deposition Energy (Heat) is released by atoms. A phase diagram can represents the various phases of compounds and the conditions (variables) that must exist for the compound to exist in the specific phases. What are the variables on each axis? Phase Diagrams Each black line represents the conditions when a phase change occurs. • Triple Point – point that exist when all three states of matter are present at the same time • Critical Point – point on a phase diagram where the liquid phase has the same density as the gas phase and are indistinguishable. • No matter what pressure or temperature is applied, it will always be a gas. http://www.kentchemistry.com/links/Matter/Phasediagram.htm You can identify the boiling and freezing point of a substance by looking at the 1 atm pressure and drawing a line. At what temperature will this substance freeze? At what substance will this substance boil?