As Emergency Responders, How Does Physical States and Property Knowledge Benefit?

As an emergency responder, it is critical to understand the basic chemistry of hazardous materials because often times they are described and expressed in its state of its chemical properties. The understanding of some chemical elements, atoms and bonding, chemical expressions and nomenclature, chemical reactions and some specific chemical properties.

Properties and Changes of States and Matter

According to the definition of ignitability in 40 CFR 261.21 (a), solid waste is defined as having a characteristic of ignitability if it displays either of these properties: (a) it is a liquid other than an aqueous solution containing less than 24 percent of alcohol by volume and obtains a flash point of less than 60 degrees Celsius (b) it is not a liquid and is capable, under standard temperature and pressure, of causing fire and friction, absorption of moisture or spontaneous chemical changes and when it is ignited, it buns so vigorously and persistently it creates a hazard. Flash point is only applied to a solid waste which is liquid. To exhibit characteristics of ignitability for a solid waste which is solid must be capable of igniting without a flame. 

There are two approaches to defining the physical states of matter. The first and classic approach is known as static. In this approach, a solid material is rigid with little or no fluid characteristics and has a fixed volume and shape. A fluid liquid is considered a liquid fluid enough to take on the shape of the container holding it, but the volume remains constant. A gas is so fluid can be contained in a closed vessel and can spontaneously take on the shape and volume of the container. For this, any liquid that is a substance is considered a liquid when it 'fails' the paint filter test (when the material is put into a specified filter material, a liquid will pass through within five minutes). The second approach is dynamic and recognizes that the current state is an interaction between the material and the current temperature. To change a state, you can do so by adding heat to a material to raise the temperature until it goes under a chemical reaction or a change of state. When there is an assumed chemically stable, solid substance, it will remain solid at all temperatures below freezing (melting) point. But, if it is heated above the melting point, it undergoes a change of state (a phase change) and then becomes liquid. 

Matter is defined in elementary courses as something that has mass and occupies volume (space). One early discovery is that for pure materials, the density of a solid (the ratio of its mass to its volume) is given a constant temperature. Later, investigators have found that this concept applies to all matter. The concept of specific gravity is useful to the hazardous material manager/ emergency responder for two reasons. First, it divides the materials into those that sink and those that float in relativity to water. Secondly, it allows us to preform the conversion from gallons to cubic feet to pounds which is required under several environmental regulations. For gases, neither the mass-to-volume density nor the specific gravity is generally reported. 

http://www.britannica.com/science/phase-state-of-matter