Terms Flashcards
What is a corrosive substance, and why is it significant?
Corrosive substances, such as acids (pH < 7) and bases (pH > 7), destroy materials and tissue, posing risks to responders and equipment.
What is air reactivity?
Air-reactive materials ignite or react violently with air, such as alkali metals or pyrophoric substances.
What is auto-refrigeration?
Auto-refrigeration occurs when rapid evaporation cools a liquid to freezing temperatures, potentially causing equipment failure or frostbite.
What are biological agents and toxins?
Biological agents are organisms (e.g., bacteria, viruses) or their toxins (e.g., ricin) that cause harm through disease or poisoning.
What are blood agents?
Blood agents, such as hydrogen cyanide (HCN), interfere with oxygen transport in the blood, causing asphyxiation.
What is the boiling point?
The boiling point is the temperature at which a liquid becomes vapor; water’s boiling point is 100°C (212°F) at 1 atm pressure.
What is a catalyst?
A catalyst speeds up a chemical reaction without being consumed, such as enzymes in biological systems.
What is a chemical change?
A chemical change alters a substance’s molecular structure, producing a new substance (e.g., combustion).
What are chemical interactions?
Chemical interactions occur when substances react together, potentially creating hazardous conditions.
What is the difference between a compound and a mixture?
Compounds are chemically bonded (e.g., H₂O), while mixtures are physically combined (e.g., air).
What is concentration?
Concentration measures the amount of a substance in a mixture, often in ppm or mg/L.
What is critical temperature and pressure related to gases?
The critical temperature and pressure define the point where a gas cannot be liquefied, no matter the pressure applied.
What is dissociation in acids and bases?
Dissociation occurs when acids or bases split into ions in water (e.g., HCl → H⁺ + Cl⁻).
What is a dose?
A dose is the amount of a substance absorbed by an organism, affecting the severity of its impact.
What is a dose-response relationship?
The dose-response relationship shows how an organism’s response changes with increasing exposure levels.
What is expansion ratio?
Expansion ratio measures how much a liquid expands when vaporized; liquid propane expands by 270 times.
What is the fire point?
The fire point is the temperature at which a liquid’s vapors sustain combustion, slightly above the flashpoint.
What are the flammable limits?
Flammable limits are the concentration range (LEL to UEL) in which a substance can ignite; methane’s range is 5-15%.
What is the flashpoint?
The flashpoint is the minimum temperature at which a liquid’s vapors ignite when exposed to an ignition source.
What is half-life?
The time it takes for half of a radioactive substance or chemical to decay or degrade.
What are halogenated hydrocarbons?
Hydrocarbons with halogen atoms (e.g., chlorine or bromine), often used as refrigerants or solvents.
What is the auto ignition temperature?
The ignition temperature is the minimum temperature at which a material ignites without an external flame.
What is an inhibitor?
An inhibitor slows or stops a chemical reaction, such as rust inhibitors for metals.
What is instability?
Instability refers to a material’s tendency to decompose or react dangerously when exposed to heat or shock.
What is the difference between ionic and covalent compounds?
Ionic compounds form by transferring electrons (e.g., NaCl), while covalent compounds share electrons (e.g., H₂O).
What are irritants?
Irritants like tear gas cause temporary pain or discomfort to the eyes, skin, or respiratory system.
What is the MSST?
The highest temperature at which a material can be safely stored without decomposition.
What is the melting/freezing point?
The temperature at which a substance changes between solid and liquid states; water freezes at 0°C (32°F).
What is miscibility?
Miscibility is the ability of liquids to mix completely, like water and ethanol.
What are nerve agents?
Nerve agents like Sarin and VX disrupt the nervous system by inhibiting acetylcholinesterase, leading to paralysis.
What is the difference between organic and inorganic substances?
Organic substances contain carbon, while inorganic substances do not.
What is oxidation potential?
Oxidation potential measures a material’s tendency to lose electrons, which indicates its reactivity.
What is persistence?
Persistence refers to how long a chemical remains hazardous in the environment; VX is highly persistent.
What does pH measure?
pH measures acidity or alkalinity on a scale of 0 (acidic) to 14 (alkaline).
What is a physical change?
A physical change alters appearance or state without changing chemical composition.
What are the physical states of matter?
Matter can exist as solid, liquid, or gas, depending on temperature and pressure.
What is polymerization?
Polymerization is a reaction where small molecules (monomers) join to form larger molecules (polymers), sometimes causing violent reactions if uncontrolled.
What is radioactivity?
Radioactivity is the emission of radiation as unstable atomic nuclei decay, measured in becquerels (Bq) or curies (Ci).
What is reactivity?
Reactivity refers to a substance’s tendency to undergo chemical changes, such as combining with other chemicals, potentially causing hazardous reactions like explosions or releases of heat.
What are riot control agents?
Riot control agents, like CS gas or pepper spray, are chemical compounds used to cause temporary irritation to eyes, skin, and respiratory systems for crowd control.
What are saturated, unsaturated, and aromatic hydrocarbons?
- Saturated hydrocarbons have single bonds (e.g., methane).
- Unsaturated hydrocarbons have double or triple bonds (e.g., ethene).
- Aromatic hydrocarbons contain benzene rings (e.g., toluene).
What is SADT?
SADT is the temperature at which a substance begins to decompose uncontrollably, potentially leading to fire or explosion.
What is solubility?
Solubility is the ability of a substance to dissolve in a solvent, such as salt dissolving in water.
What is the difference between a solution and a slurry?
A solution is a homogeneous mixture of substances, while a slurry is a mixture of solids suspended in a liquid.
What is specific gravity?
Specific gravity is the ratio of a substance’s density to the density of water; water has a specific gravity of 1.
What does strength refer to in chemistry?
Strength refers to the concentration or effectiveness of a substance, such as a strong acid releasing more hydrogen ions (H⁺).
What is sublimation?
Sublimation is the process where a solid changes directly to a gas without becoming a liquid first, such as dry ice turning into carbon dioxide gas.
Why is the temperature of a product significant?
The temperature of a product affects its state, reactivity, and pressure, influencing storage and handling safety.
