Unit 4 Chemistry of Fire This will be as basic as it gets. Do you remember the Periodic Table? We will stay very basic We will look at the states of matter and why they are important to firefighting We will discuss the atom but thats about it for the atom If you want a Chemistry Class-Take Chemistry! Three States 1. Solid 2. Liquid 3. Gas Two Types 1. Organic 2. Inorganic Compounds are made up of two or more elements The Periodic Table shows all the existing elements An example of a compound is wood: it consists of the elements Hydrogen, Carbon, and Oxygen, a little nitrogen and other elements Atoms and molecules are smaller units of the elements Atoms are made up of a nucleus surrounded by three subatomic particles: Protons Neutrons Electrons Atoms are held together by electrical charge Molecules are made up of atoms Compounds will break into smaller compounds or molecules when heated When heated, a compound will start to decompose- the temperature needed to start the decomposition process is called decomposition temperature When a compound starts breaking down or decomposing it is occurring at the molecular level. The heat causes the molecules to change. The molecules start to convert to a gaseous state- that is what is actually burning Organic Compounds contain hydrocarbons meaning they are derived from living organisms Inorganic Compounds are naturally occuring Examples of Inorganic Compounds are: Copper, Zinc, Granite, Lead Boiling Point- The temperature in which the molecules in a liquid begin to break the surface tension of the liquid and begin to change to vapor Vapor Pressure- The pressure placed on a closed container from the molecules being released by the liquid in vapor form Vapor Density- Greater than 1 will hang lower to the ground. (Heavier than air) Flash Point Fire Point Solubility Specific Gravity- Greater than one will sink in water Explosive Range (To rich or to lean- it wont burn) Thermal Imaging Capabilities Engineer Assist in extinguishment or stay by pump? Anything Else? Conduction Convection Radiant Direct Flame Impingement