Chemistry

Decomposition of Ammonium Compound

Chemistry of Hazardous Chemicals Which of the indicators would NOT communicate to a first on-the-scene responder of the presence of a simple oxidizer?The number 6.1 as a component of a basic description of a hazardous material listed on a shipping paper2. What product is sometimes selected instead of chlorine to bleach paper pulp and produce white wheat flour?Chlorine dioxide3. What is the principal risk associated with exposure to chlorine dioxide?It can cause inhalation toxicity4. Clorox is an aqueous solution containing what percentage of sodium hypochlorite?6%5. Which of the following statements regarding oxidation numbers is FALSE?The oxidation number of each atom in an element is zero, such that the oxidation number of Cl2 is +2.6. What two chemicals can be used medicinally to cure dermatitis (from a bacterial/fungal origin) and eliminate or reduce effluent gases from many industrial sources?Metallic sodium permanganate and potassium permanganate7. When heated, all metallic hypochlorites decompose and produce oxygen. Considering this, what happens when the decomposition reaction occurs at an incident involving fire?The oxygen supports combustion reactions.8. What adverse health effect has been associated with the absorption of hexavalent chromium compounds into the body?It has been linked to lung cancers9. Calcium hypochlorite is known by what name when it used as a disinfectant in swimming pools?HTH10. Potassium dichromate is a strong oxidizer and, therefore, incompatible with which of the following substances?Hydrochloric acidDecomposition of ammonium compoundAmmonium compounds are identified by an ammonium ion in their composition. They quickly lose stability when exposed to heat, hence decompose in two ways. One of them is the decomposition of ammonium compound into its respective initial compounds that were used to form it. Only simple compounds of ammonia that are regarded less hazardous are decomposed by this method. A good example to illustrate this method is the decomposition of ammonium chloride (NH4Cl (s)) into hydrogen chloride (HCl (g)) and ammonia (NH3 (g)). Equation 1 below illustrates the decomposition of this decomposition process.NH4Cl (s) NH3 (g) + HCl (g) (1)The second method is the oxidation-reduction process. Most of the compounds decomposed by this method react explosively to thermal decomposition. For this reason, DOT does not allow carriers to transport them. A good example of these compounds is the ammonium dichromate (NH4)2Cr2O7(s), which decompose to chromium (III) oxide Cr2O3 (s), nitrogen (N2 (g)) and water (H2O (l)) on heating as illustrated in equation 2.(NH4)2Cr2O7(s) Cr2O3(s) + N2 (g) + 4H2O (l) (2)According to Vorsina amp. Mikhailov (1996), when ammonium persulfate is thermally decomposed, the following chemical reaction shown in equation 3 takes place.(NH4)2S2O8 (NH4)2S2O7 + 0.5O2 (3)Why OSHA requires the segregation of ammonium nitrate for sulfur or finely divided metalsSulfur and finely divided metals are flammable. hence ignite readily at normal burning temperatures. In this regard, they can quickly expose ammonium nitrate to fire if not segregated. However, exposing bulk ammonium nitrate to fire may result in an explosive thermal decomposition of this compound to various products, including the toxic nitrogen dioxide (Meyer, 2010). As such, OSHA requires the segregation as mentioned earlier to prevent explosion of ammonium nitrate and life-threatening gases like nitrogen dioxide.OSHA requires employers to protect flooring and handling areas in buildings against impregnation by ammonium nitrateThis precaution is meant to ensure that ammonium nitrate does not leak into areas that it might be confined in case of fire. As seen from recent research (Meyer, 2010), exposing bulk ammonium nitrate to fire scenes results into its thermal decomposition at explosive rates, from which it might also produce the toxic nitrogen dioxide gas. Why firefighters recommend the use of a deluging volume of water when extinguishing an oxidizer-supported fireWater is the primary solvent used to dissolve solutes. Additionally, metallic oxidizers are readily soluble in water. For this reason, their chemical reactivity is eliminated through diluting them in water. In doing this, the oxidation-reduction reaction of oxidizers is slowed down. As result, water as a solvent turns out as an excellent extinguisher of an oxidizer-supported fire. What may happen to a large (i.e., 30-50lb) container of trichloro-s-triazinetrione, or calcium hypochlorite, if it is left to sit in the water and muckThe compromised container will cause leakages of trichloro-s-triazinetrione or calcium hypochlorite stored in it. Being a strong oxidizing agent, it may cause thermal explosion. The primary rationale to support this argument is that the water left behind after the firefighters efforts to stop a combustion initiated by an oxidizing agent, tend to evaporate if it is unattended to. For this reason, trichloro-s-triazinetrione or calcium hypochlorite that leaks out after evaporation of this water is left in a dry state, implying that no solvent will be available to neutralize it as an effort to slow down this oxidizer’s oxidation-reduction reaction rate. As such, the leaked out trichloro-s-triazinetrione or calcium hypochlorite will eventually re-ignite the just ended fire. For this reason, Meyer (2010) recommends damming or diking of the runoff water used to dilute the oxidizer when responding to a fire scene to ensure that any oxidizer left behind will be readily neutralized before getting an exposure to high temperature that might result in its explosion.ReferencesMeyer. (2010). Chemistry of some oxidizers. https://www.sendspace.com/file/6f3xd3 Vorsina, I. A., amp. Mikhailov, Y. I. (1996). Kinetics of Thermal Decomposition of Ammonium Persulfate. Russian Chemical Bulletin, 539.

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