Liquids<br />Chapter 12.1<br />Objectives<br />Describe the motion of particles in liquids and the properties of liquids according to the kinetic-molecular theory.<br />Discuss the process by which liquids can change into a gas. Define vaporization.<br />Discuss the process by which liquids can change into a solid. Define freezing.<br />
Liquids<br />Examples:<br />Oceans, lakes, rivers<br />Hard to believe – liquids are the least common state in the universe<br />Why?<br />Narrow temperature range they can exist in!<br />
Properties of Liquids and Kinetic-Molecular Theory<br />Definite volume, take shape of container<br />According to Kinetic-Molecular Theory<br />Liquid’s particles are:<br />In constant random motion<br />Closer together than gases, there are attractive forces<br />More ordered than gases, so particles are held together, but do have mobility.<br />Fluid: substance that can flow and therefore take the shape of its container<br />
Relatively High Density<br />Thousands of times denser than gases<br />Slightly less dense than solids<br />Due to the close arrangement of liquid particles<br />
Relative Incompressibility<br />Less compressible because particles are packed together<br />Ability to Diffuse<br /><ul><li>Liquids will diffuse in other liquids it can dissolve in.
Much slower in liquids than in gases</li></li></ul><li>Surface Tension<br />Force that tends to pull adjacent parts of a liquid’s surface together, thereby decreasing surface area to the smallest possible size.<br />Water has high surface tension<br />Hydrogen bonding are strong intermolecular forces<br />Capillary Action<br />Attraction of the surface of a liquid to the surface of a solid<br />
Evaporation and Boiling<br />Vaporization:<br />Process by which a liquid or solid changes to a gas<br />Evaporation:<br />Process by which particles escape from the surface of a non-boiling liquid and enter the gas state.<br />Boiling:<br />Change in liquid to bubbles of vapor that appear throughout the liquid.<br />
Formation of Solids<br />When liquid is cooled, average kinetic energy decreases<br />Particles slow down<br />Attractive forces pull into an orderly arrangement<br />Freezing (solidification):<br />Physical change of a liquid to a solid by removal of heat.<br />