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Chemistry and Hazards of Hazardous Materials and Weapons of Mass Destruction Chapter Contents Chemistry and Hazards of Hazardous Materials and Weapons of Mass Destruction Chapter Contents Case History ................................145 Polymerization ...........................................................173 atoms ...........................................146 Decomposition ..........................................................174 Periodic table of elements ..................146 Synergistic Reactions ................................................174 Four significant Families ....................147 The Fundamentals of a Reaction ...............................175 Group I – The Alkali Metals .......................................153 Common Families of Hazardous Materials .....................................176 Group II – The Alkaline Earths ...................................154 Inorganic Compounds ...............................................176 Group VII – The Halogens .........................................155 Organic Compounds ..................................................176 Group VIII – The Noble Gases ...................................156 Oxidizers ....................................................................180 Matter ..........................................156 Reactive Materials .....................................................181 Elements ....................................................................158 Corrosives .................................................................185 Compounds ...............................................................160 special Hazards of Chemicals and Weapons Mixtures .....................................................................162 of Mass Destruction ........................186 Bonding.........................................164 Chemical Warfare Agents ..........................................186 The Octet/Duet Rule ..................................................165 Biological Agents and Toxins.....................................190 Stability of Elements and Compounds ......................166 Explosives and Incendiaries ......................................192 Diatomic Molecules (Compounds) ............................166 Pesticides and Agricultural Chemicals ......................194 Ionic Bonds ................................................................166 radiation .......................................194 Covalent Bonds ..........................................................168 Non-Ionizing ..............................................................194 Resonant Bonds ........................................................168 Ionizing ......................................................................195 Bond Energy ..............................................................169 Chapter summary ............................198 Bonding in Haz Mat Response...................................169 review Questions ............................198 reactions ......................................170 Exothermic and Endothermic Reactions ...................171 Oxidation and Combustion ........................................171 142 Chapter 4 • Chemistry and Hazards of Hazardous Materials and Weapons of Mass Destruction Key terms 4 Activation Energy ....................................175 Inorganic Peroxide ..................................181 Air-Reactive Material ...............................182 Ion .............................................................167 Anions ......................................................167 Ionic Bonds ..............................................166 Atom..........................................................146 Mixture ......................................................162 Binary Salt ................................................161 Molecule ...................................................158 Bond Energy ............................................169 Monomer ..................................................173 Catalyst .....................................................173 Neutron .....................................................146 Cations .....................................................167 Nucleus .....................................................146 Compound ................................................158 Organic Peroxide .....................................181 Covalent Bond .........................................168 Persistence ..............................................186 Deflagration .............................................193 Pesticide ...................................................194 Detonation ................................................193 Polymer ....................................................173 Diatomic Molecule ...................................158 Polymerization .........................................173 Dissociation .............................................185 Proton .......................................................146 Electron ....................................................146 Reactive Material .....................................171 Element .....................................................147 Resonant Bond ........................................168 Explosive ..................................................192 Shells ........................................................146 Half-Life ....................................................196 Slurry ........................................................164 Inert Gas ...................................................156 Solution ....................................................162 Inhibitor .................................................... 174 Water-Reactive Material ..........................182 NFPa® Competencies NFPA® 472 References 7.2.1.4 7.2.2.2(2, 4, 5, 7-10, 13, 20, 23-27, 30, 31, 33, 36-37, 40-42, 44, 52) Chapter 4 • Chemistry and Hazards of Hazardous Materials and Weapons of Mass Destruction 143 Chemistry and Hazards of Hazardous Materials and Weapons of Mass Destruction Learning objectives 1. Define atoms. 2. Describe the basic arrangement of the periodic table of elements. 3. Explain the four significant families of elements. 4. Describe matter. [NFPA® 472, 7.2.2.2(10, 36, 44)] 5. Explain the concept of bonding. [NFPA® 472, 7.2.2.2(24, 25)] 6. Explain the various types of reactions. [NFPA® 472, 7.2.2.2(7-8, 23, 37)] 7. Describe common families of hazardous materials. [NFPA® 472, 7.2.2.2(2, 4, 9, 13, 27, 31, 41, 42)] 8. Identify special hazards of chemicals and weapons of mass destruction. [NFPA® 472, 7.2.2.2 (4, 5, 26, 30, 33, 40, 52)] 9. Discuss radiation. [NFPA® 472, 7.2.1.4, 7.2.2.2(20)] 144 Chapter 4 • Chemistry and Hazards of Hazardous Materials and Weapons of Mass Destruction Chapter 4 Chemistry and Hazards of Learning objectives Hazardous Materials and Weapons of Mass Destruction Case History A cargo tank carrying styrene was involved in a serious accident on a busy highway in a highly populated area. A haz mat team was called to the scene. Visual assessments and detection and monitoring determined that the tank had not breached and no leaks had occurred. The chemical company responsible for shipping the styrene was contacted, and it was deter- mined that the styrene was shipped with a time-sensitive inhibitor. This meant that the natural polymerization of the styrene would eventually overcome the inhibitor, potentially resulting in a rapid, runaway polymerization reaction. This set a timetable for mitigation of the incident that was under 24 hours. Plans for a worst-case scenario were developed and preliminary evacuations conducted. Until the chemical shipper’s own emergency response personnel arrived at the scene to take over, the haz mat team monitored the tank with a temperature gun to detect any rapid changes in temperature that might indicate an accelerating reaction. While it is not critical for hazardous materials technicians to be chemistry ex- perts, some knowledge of chemistry can help hazardous materials technicians comprehend how and why chemicals behave the way they do. This is an impor- tant skill-set, especially when reference sources are not immediately available. This chapter provides a brief and basic introduction to chemistry — enough to address terminology and concepts that will make it easier to understand the behavior of hazardous materials. As much as possible, these concepts are pre- sented in terms of what it means to the hazardous materials technician in the field. For example, the Periodic Table of Elements (also known as the Periodic Table) is examined to provide clues that may help responders predict how vari- ous elements will behave. Examples provided in the chapter are used to illustrate concepts and are not meant to be all-inclusive. For instance, in presenting the Periodic Table of Elements, the chapter highlights four “families” of elements that have similar characteristics and then explores one or two elements within each family. Out in the field, hazardous materials technicians must be diligent about checking reference sources rather than relying solely on generalizations in this book or any other. Chapter 4 • Chemistry and Hazards of Hazardous Materials and Weapons of Mass Destruction 145 This chapter explores the following topics: A Helium Atom • Atoms and molecules • The Periodic Table of Elements • Four significant families • Matter Proton • Bonding • Reactions • Common families of hazardous materials Nucleus • Radiation Neutron Atoms The basic building block of any substance is theatom . Electron Shell Electron Every element and compound is
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