Home

Halogenated phenol use

Protonation of Gaseous Halogenated Phenols and Anisoles

Central pathways of aerobic catabolism of phenol and its

Phenols and Related Compounds Phenolic compounds used as antiseptics or disinfectants include pure phenol and substitution products with halogens and alkyl groups. They act to denature and coagulate proteins and are general protoplasmic poisons. Phenol (carbolic acid) is one of the oldest antiseptic agents Halogenated phenols aren't very water soluble, and so if your TCP is sold as an aqueous cream or a liquid, it may well contain different antimicrobial compounds than an oil-based ointment. On the toxicity problem, he points out that halogenated phenols aren't absorbed by the skin very well, so using them externally shouldn't cause a problem

  1. The GC system may also be set up to use a single detector when an analyst is looking for only halogenated compounds (HECD) or aromatic compounds (PID). 2.2 Tentative identifications are obtained by analyzing standards under the same conditions used for samples and comparing resultant GC retention times. Confirmator
  2. Phenol is commonly used in surgeries for ingrown toenails. It's used on more severe ingrown toenails that don't respond to other treatments. The phenol, in the form of trichloroacetic acid, is used..
  3. Halogenated phenols act on all pathogenic micro-organisms similarly and to approximately the same degree - i.e. they are non-specific, their activity is not appreciably reduced by the presence of relatively large amounts of non-living organic matter, their relatively simple chemical constitution means that their use is not liable to encourage the emergence of strains of micro-organisms adapted to resist their action
  4. Trichlorophenylmethyliodosalicyl was replaced as the active ingredient by a mixture of phenol and halogenated phenols in the 1950s. The liquid form of TCP is one of the best-known brands of antiseptic in the UK, and its distinctively strong medicinal odour can be identified by many as a generic antiseptic smell
  5. ed using isolated rat liver mitochondria. The relationship between physiochemical properties of phenolic compounds and their effects on mitochondria were studied. Phenol and p-halogenated p

US2811566A US463813A US46381354A US2811566A US 2811566 A US2811566 A US 2811566A US 463813 A US463813 A US 463813A US 46381354 A US46381354 A US 46381354A US 2811566 A US2811566 A US 2811566A Authority US United States Prior art keywords reaction halogen alkenylphenols alkenylphenol chlorine Prior art date 1954-10-21 Legal status (The legal status is an assumption and is not a legal conclusion In industry, phenol is used as a starting material to make plastics, explosives such as picric acid, and drugs such as aspirin. The common phenol hydroquinone is the component of photographic developer that reduces exposed silver bromide crystals to black metallic silver In general, halogenated phenols and biphenols have strong antibacterial properties and, therefore, many of them have been used in antiinfective topical formulations and germicidal soaps [17,18] phenols, and the tests show that halogenated phenols, mainly brominated species, are found in produced water after treatment with chlorine dioxide. Due to potential environmental risk from halogenated organic contaminants, the use of chlorine dioxide as phenol and H2S scavenger is not recommended. Phisohex must not be used on persons who have demonstrated primary light sensitivity to halogenated phenol derivatives because of the possibility of cross-sensitivity to hexachlorophene. Phisohex should be kept out of the eyes. If contact occurs, the patient should rinse with cold water as soon as possible and contact a physician..

Efficient removal of halogenated phenols by vacuum-UV

halogenated benzenes, benzoates and phenols. Materials and methods Computational methods Ab initio quantum chemical calculations to estimate DH f o and So values of phenol and all chlorinated and brominated phenol congeners were performed with the Gaussian 03 software, Revision E1 (Frisch et al. 2003). The use of this software for. The major hazards encountered in the use and handling of 2-chlorophenol stem from its toxicologic properties. Toxic by all routes (ie, ingestion, inhalation, dermal contact), exposure to this colorless to yellow-brown liquid may occur from its use as an intermediate in the manufacture of dyes and higher chlorinated phenols, and as solvent or as. Properties Acidity. Phenols are more acidic than typical alcohols. The acidity of the hydroxyl group in phenols is commonly intermediate between that of aliphatic alcohols and carboxylic acids (their pK a is usually between 10 and 12). Deprotonation of a phenol forms a corresponding negative phenolate ion or phenoxide ion, and the corresponding salts are called phenolates or phenoxides. Search emc: Enter medicine name or company. GO Advanced Search >

Phenols and Related Compounds - Pharmacology - Veterinary

A method was developed for the extraction of lipids and analysis of halogenated phenols and alkylphenols in marine organisms. The extraction efficiency was evaluated by comparing the extractable lipid content and the recovery of 13 added phenols from three different marine species (herring, cod, and blue mussel), with the corresponding results from three well-established extraction procedures. Phenol and its non-halogenated derivatives have been used for over 100 years as antiseptics to control growth of microorganisms. Their importance in controlling microbial growth in foods, however, has been recognized only recently. Phenolic compounds important in foods may be classed conveniently into three categories

The new halogenated butyl rubber when cured with heat reactive phenolic resin cure system, typically including a metal oxide such as zinc oxide, has improved performance properties including.. Halogenated phenols such as chlorinated phenols, especially tetrachlorophenols and pentachlorophenol, are valuable fungicides that are conveniently prepared by the direct halogenation of phenol or halogenated phenols in the presence of various catalysts such as AlCl 3, FeCl 3, activated carbon and quinoline, tellurium and various salts thereof. A growing number of studies have reported phenolic halogenated compounds (PHCs) that are retained in the blood of humans and wildlife. These PHCs may be industrial chemicals; metabolites thereof, as in the case with polychlorobiphenylols (OH-PCBs); or of natural origin. The present study was aimed t Phenol reacts with dilute nitric acid at room temperature to give a mixture of 2-nitrophenol and 4-nitrophenol. With concentrated nitric acid. With concentrated nitric acid, more nitro groups substitute around the ring to give 2,4,6-trinitrophenol (old name: picric acid)

(PDF) Disinfection by-products formation during wastewater

Halogenated aromatic epoxy resins are disclosed wherein the halogen atoms are in the meta position with respect to a glycidyl ether group attached to an aromatic ring. Advanced epoxy resins are disclosed which result from the reaction of a relatively low molecular weight epoxy resin and a polyhydric phenol wherein at least one of the reactants. Halogenated phenol toxicity to tetrahymena pyriformis was related to E LUMO, V m, and q − (Peng and Liu 2009). In general, toxicity of halogenated phenols was related to electronic properties. The toxicity of diphenyl ethers is mainly related with logK ow. Halogenated diphenyl ethers also have hydrophobicity-dependent toxicity Use as an occlusive dressing, wet pack, or lotion. Routine prophylactic total body bathing. Use as a vaginal pack or tampon, or on any mucous membranes. Known primary light sensitivity to halogenated phenol derivatives

What exactly does the antiseptic TCP contain

Phenol and its non-halogenated derivatives have been used for over 100 years as antiseptics to control growth of microorganisms. Their importance in controlling microbial growth in foods, however, has been recognized only recently. Phenolic compounds important in foods may be classed conveniently into three categories The following spent non-halogenated solvents: Cresols and cresylic acid, and nitrobenzene; all spent solvent mixtures/blends containing, before use, a total of ten percent or more (by volume) of one or more of the above non-halogenated solvents or those solvents listed in F001, F002, and F005; and still bottoms from the recovery of these spent.

What is Phenol? Medical Uses, Health Benefits, and Risk

Phenol in low concentrations is used as a disinfectant in household cleaners and mouthwash. Phenol used as a slimicide (a chemical toxic to bacteria and fungi characteristic of aqueous slimes) is a type of disinfectant. The largest single use of phenol is as an intermediate in the production of phenolic resins 4.5. 5. Flame retardant (FR) plastics are essential to devices we use every day, providing a valuable tool in fire prevention, but their technology is complex. While some resins are inherently flame resistant, others need special additives to minimize the propagation of smoke and flames

Since the para position of phenol, which is the site of the indophenol reaction, is occupied by halogen atoms, e.g. Cl, Br, and I, para-halogenated phenols are expected to be undetectable by the indophenol reaction. As a result, the suggested color assay showed superior selectivity towards phenol, in the presence of a halogenated phenol pHisoHex must not be used on persons who have demons trated primary light sensitivity to halogenated phenol derivatives because of the possibility of cross -sensitivity to hexachlorophene. pHisoHex should be kept out of the eyes. If contact occurs, the patient should rinse with cold water as soon as possible and contact a physician For the synthesis of compound 3ar, the usage of 2-bromoethanol, 2-chloroethanol, or 2-iodoethanol contributed similar yields, wherein the use of 2-iodoethanol slightly increased the yield of 3ar. The longer alkyl chain resulted in lower yield. The scope of the present investigation was extended to flavone derivatives In 2020, the total trade exchange of Carboxylic Acids with Phenol Function but without other Oxygenated Function, their Anhydrides, Halides, Peroxides, Peroxyacids and their Halogenated, Sulfonated, Nitrated or Nitrosated Derivatives (Excl. Salicylic Acid, O-Acetylsalicylic Acid, their Salts and Esters) in Mexico (including international purchases and sales) was US$13.4M Halogenated, sulphonated, nitrated or nitrosated derivatives of phenols or phenol-alcohols. Halogenated, sulphonated, nitrated or nitrosated derivatives of phenols or phenol-alcohols. Home The Platform The API About Login + 31 85 303 68 25. EN NL. Free trial

TCP Antiseptic Liquid - Summary of Product Characteristics

(a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as halogenated bisphenol A, polymer with bisphenol A diglycidyl ether and epoxidized phenol-formaldehyde resin, alkenoate (PMN P-15-767) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this section A simple reaction scheme of halogenated phenol oxidative dehalogenation by a flavin-dependent monooxygenase which occurs via the reaction of the C4a-hydroperoxy-flavin intermediate. For a single-component enzyme like PcpB from S. chlorophenolicum , the substrate is pentachlorophenol and the flavin is reduced via the blue pathway (Hlouchova et. genated phenol, halogenated aniline and halogenated benzoate derivatives which serve as substrates for enzymes in the next stage (middle pathway). The middle pathway deals mainly with halide removal and activation of aromatic rings by incorporation of oxygen atom (in the case of aerobes). Halogen atom removal is the key ste As an important branch of halogenated bisphenol compounds, the halogenated bisphenol monosubstituted-ether compounds have received a lot of attention in environmental health science because of their toxicity and variability. In this study, a synthetic method for bisphenol monosubstituted-ether byproduct libraries was developed Phenol = 1.47 13. DISPOSAL CONSIDERATIONS Waste Disposal Method Dispose of material in accordance with all federal, state, and local regulations. Contaminated Packaging Dispose of in accordance with all federal, state and local regulations. Chemical Name Phenol - 108-95-2 Chemical NameRCRA - Halogenated Organic Compounds RCRA - P Series Wastes.

Harmonized Tariff Schedule of European Uninon (2021) Chapter 29. CN Codes of heading 2908. CN Code. Description 2907 2909. 2908.00.00.00. Halogenated, sulphonated, nitrated or nitrosated derivatives of phenols or phenol-alcohols. 2908.11.00.00. - Derivatives containing only halogen substituents and their salts Tcp Antiseptic Liquid is used for Ingrown toe and fingernails and other conditions.Tcp Antiseptic Liquidmay also be used for purposes not listed in this medication guide. Tcp Antiseptic Liquidcontains Halogenated Phenols and Phenol as active ingredients. Tcp Antiseptic Liquidworks by numbing the painful or irritated areas

4-Bromo-2,6-bis-hydroxymethyl-phenol is a halogenated phenol derivative for proteomics research. Technical Information. Physical State : Solid. Storage : Store at room temperature. Safety Information. For Research Use Only. Not Intended for Diagnostic or Therapeutic Use Phenol, Liquified Created by Global Safety Management, Inc. -Tel: 1-813-435-5161 - www.gsmsds.com SECTION 1 : Identification of the substance/mixture and of the supplier Product name : Phenol, Liquified Manufacturer/Supplier Trade name: Manufacturer/Supplier Article number: S25463 Recommended uses of the product and uses restrictions on use Mechanistic aspects regarding the direct aqueous environmental photochemistry of phenol and its simple halogenated derivatives. A review. Environment International, 2009. Kaya Forest. Sierra Rayne. Kaya Forest. Sierra Rayne. Download PDF. Download Full PDF Package. This paper In the present study the oxidative dehalogenation of a para-halogenated phenol was studied using pentafluorophenol and its non-para-halogenated analogue 2,3,5,6-tetrafluorophenol as model compounds. 19F NMR was used to characterize the metabolite patterns. In order to study the primary oxidation products.. Various halogenated pyridines (2-fluoropyridine, 2-chloropyridine, 2-bromopyridine, 3-bromopyridine, 2,5-dibromopyridine, and 3,5-dibromopyridine) are subject to catalytic reduction and substitution under DOW-phenol conditions; copper(I) benzoate is shown to play a key role in these processes

TCP Liquid Antiseptic Original 200ml British Shop

TCP (antiseptic) - Wikipedi

Catalytic reduction of polyhalogenated aromatic hydrocarbons by Cu(I) under Dow-Phenol conditions. Catalysis Today, 1996. Wim Buijs. Download PDF. Download Full PDF Package. This paper. A short summary of this paper. 37 Full PDFs related to this paper. READ PAPER Human and zebrafish PPARγ activation by halogenated-BPAs in vivo and in vitro. (A-F) GFP fluorescence and bright field (insert) images (lateral view) of 28 hpf Tg(hPPARγ-eGFP) zebrafish embryos treated for 24 h with DMSO (A), RGZ (B, C), TBBPA (D, E) and TCBPA (F). (G) Dose-response curves of quantified GFP expression in 28 hpf Tg(hPPARγ-eGFP) zebrafish embryos exposed to 0.1% DMSO, RGZ. The key difference between phenol and phenyl is that phenol has a hydroxyl group whereas phenyl has no hydroxyl group.. Phenol is an aromatic alcohol.It has the chemical formula C 6 H 5 OH. Therefore, the chemical structure of the phenol molecule has a benzene ring and a hydroxyl group (-OH) attached to it. Phenyl is a derivative of phenol; if we remove the hydroxyl group from the phenol. Phenol is the simplest of the phenols, with one of the attached hydrogen atoms on a benzene ring replaced with a $-OH$ group. It is a slightly soluble grey solid, with the solubility due to the polar $-OH$ group, able to form hydrogen bonds with the water molecules. In everyday use, phenol can be used in detergents, antiseptics and aspirin 4-Chlorophenol for synthesis. CAS 106-48-9, chemical formula 4- (Cl)C₆H₄OH. H302 + H312 + H332: Harmful if swallowed, in contact with skin or if inhaled. H314: Causes severe skin burns and eye damage. H411: Toxic to aquatic life with long lasting effects

Effect of phenol and halogenated phenols on energy

Halogenated Phenols + Phenol (1311050V0) Part of chapter 13 Skin, section 13.11 Skin cleansers,antiseptics and desloughing agents, paragraph 13.11.5 Phenolics High-level prescribing trends for Halogenated Phenols + Phenol (BNF code 1311050V0) across all GP practices in NHS England for the last five years If halogenated, they should be collected in container B. For solid residues use container C. Safety Information; Reagents, Chemicals and Labware > Organic Synthesis > Organic Synthesis Product Groups > Phenols and Phenol Ethers > Halogenated Phenols and Halogenated Phenol Ethers The 2007 Import and Export Market for Phenols and Phenol-Alcohols, and Their Halogenated, Sulfonated, Nitrated or Nitrosated Derivatives in South Korea [Parker, Philip M.] on Amazon.com. *FREE* shipping on qualifying offers. The 2007 Import and Export Market for Phenols and Phenol-Alcohols, and Their Halogenated, Sulfonate Phenol is mainly used as an intermediate in organic synthesis. In this, phenol essentially serves as a raw material for the production of bisphenol A, phenolic resins, alkylphenols and caprolactam. It is also used for salicylic acid, nitrophenols, diphenyl ethers, halogenated phenols and other chemicals

US2811566A - Halogenated phenols - Google Patent

5-Chloro-2- (2,4-dichlorophenoxy)phenol MSDS (material safety data sheet) or SDS, CoA and CoQ, dossiers, brochures and other available documents. SDS. CoA. CAS #: 3380-34-5 EC Number: 222-182-2 Molar Mass: 289.5 g/mol Hill Formula: C₁₂H₇Cl₃O₂. 816100 The 2013 Import and Export Market for Phenols and Phenol-Alcohols, and Their Halogenated, Sulfonated, Nitrated or Nitrosated Derivatives in Czech Republic: Economics Books @ Amazon.co The 2011 Import and Export Market for Halogenated, Sulfonated, Nitrated, or Nitrosated Phenol or Phenol-Alcohol Derivatives in Israel: International, Icon Group: Amazon.sg: Book

A chemical reaction or process which results in the formation of a chemical bond between a halogen atom and another atom. Reactions resulting in the formation of halogen-carbon bonds are especially important. The halogenated compounds produced are employed in many ways, for example, as solvents, intermediates for numerous chemicals, plastic and. The degradation of phenols by a methanogenic consortium was revealed to be slower and more difficult with the substitution of halogenated compounds in phenol groups . Nevertheless, anaerobic microorganisms could overcome initial inhibition by 2, 4-dibromophenol and this inhibition could be eliminated when microbes were pre-incubated with the. The European Union has banned the use of halogenated FR additives Poly(phenol) based materials as FR's • Phenolic monomers* with radical quenching potential can be oligomerized Avoid leaching of monomers Increase concentration of radical quencher Phenol. Related Pages. Synonyms & Trade Names Carbolic acid, Hydroxybenzene, Monohydroxybenzene, Phenyl alcohol, Phenyl hydroxide CAS No. 108-95-2 RTECS No. SJ3325000. DOT ID & Guide. 1671 153(solid) 2312 153(molten) 2821 153(solution) Formula. C₆H₅OH. Conversion. 1 ppm = 3.85 mg/m 3. IDLH. 250 ppm. their use in a variety of applications the addition of FR materials is inevitable. Halogenated compounds are one of the most commonly used class of FRs. However halogenated FRs are environmentally persistent and generate toxic, corrosive gases during combustion that threaten both air and water ecosystems

Phenol and Phenol Derivatives 2. Alcohols 3. Halogens 4. Heavy Metal and their Compounds 5. Aldehydes 6. Gaseous Agents 7. Dyes 8. Detergents 9. Quaternary Ammonium Compounds. Antimicrobial Chemical Agent # 1. Phenol and Phenol Derivatives: Phenol is obtained by distillation of coal-tar. It is credited to be the first disinfectant used in the. Phenol is a member of a class of organic compounds with the same name, Phenols. Phenol is widely used in a lot of industries for varied purposes. Phenol is the most commonly used disinfectants since ancient times. It has got amazing antiseptic properties too. Phenol is proven to be effective anti-bacterial, anti-fungi and anti-viral agent EPA Hazardous Waste Number: Hazardous Waste from non-specific sources: F001: The following spent halogenated solvents used in degreasing: Tetrachloroethylene, trichloroethylene, methylene chloride, 1,1,1- trichloroethane, carbon tetrachloride, and chlorinated fluorocarbons; all spent solvent mixtures/blends used in degreasing containing, before use, a total of ten percent or more (by volume.

3-{[(3,5-dichloro-4-fluorophenyl)carbamoyl]amino}-2

Phenols. Phenols are hydroxy aromatic compounds where one or more hydroxyl group are directly attached to the carbon atoms of the benzene ring, Phenol is an organic compound which has a great industrial importance, It is used as a starting material for the synthesis of many aromatic compounds such as polymers, dyes, disinfectants, salicylic acid derivatives (as aspirin) & picric acid Binding of Phenol and Differently Halogenated Phenols to Dissolved Humic Matter As Measured by NMR Spectroscop phenol stayed intact without any sign of degradation, the only change observed was a slow and well known catalyst deactivation. Later, I also had some chance to gain some insight as to why this reaction did Oxidation of Halogenated and Polycyclic Aromatic Hydrocarbon Temporal distributions of functional microbes and putative genes associated with halogenated phenol anaerobic dehalogenation and further mineralization Zhi-ling Li , ab Jun Nan , a Jia-qi Yang , a Xiao Jin , c Arata Katayama * bc and Ai-jie Wang * a

(2000). Two Diketopiperazines and One Halogenated Phenol from Cultures of the Marine Bacterium, Pseudoalteromonas luteoviolacea. Natural Product Letters: Vol. 14, No. 6, pp. 435-440 3D-QSAR Study on Acute Toxicity of Halogenated Phenol to Green Fluorescent Protein Using CoMFA and CoMSI halogenated phenol translation in English-Greek dictionary. Cookies help us deliver our services. By using our services, you agree to our use of cookies Halogenated phenols (HPs) and nitrophenol (NP) are persistent pollutants resulting from anthropogenic activities including the use of agro- and household chemicals such as pesticides, herbicides and flame retardants Phenolic was the first plastic material molded by Rebling. Since 1961, Rebling has continued to mold this heat resistant thermoset plastic using both the transfer and injection molding processes. The ability of phenolic to maintain its mechanical and electrical properties at high operating temperatures is the principal reason for its use today

phenol Definition, Structure, Uses, & Facts Britannic

What Goes in Chemical Waste Containers. Chemical wastes can be collected in several different types of containers for disposal. The NIH chemical waste contractors will provide 3 or 5 gallon plastic solvent safety cans (for flammable solvent mixtures), 3 or 5 gallon blue plastic carboys for liquid wastes and a 5 gallon plastic pail for gels and. HS Code Of Chapter 2907 , List Of Hs Codes For PHENOLS; PHENOL-ALCOHOLS MONOPHENOLS: (PHENOLS, PHENOL-ALCOHOLS, AND THEIR HALOGENATED, SULPHONATED, NITRATED OR NITROSATED DERIVATIVES), Free Search Indian HS Classification Halogenated, sulphonated, nitrated or nitrosated derivatives of phenols or phenol-alcohols. Cookies on HMRC services. We use some essential cookies to make our services work. We would like to set additional cookies so we can remember your settings, understand how people use our services and make improvements..

The World Market for Phenols and Phenol-Alcohols, and Their Halogenated, Sulfonated, Nitrated or Nitrosated Derivatives: A 2007 Global Trade Perspective [Parker, Philip M.] on Amazon.com. *FREE* shipping on qualifying offers. The World Market for Phenols and Phenol-Alcohols, and Their Halogenated, Sulfonated, Nitrated or Nitrosated Derivatives: A 2007 Global Trade Perspectiv Halogenated, Sulphonated, Nitrated Or Nitrosated Derivatives Of Phenols Or Phenol- Alcohols - Derivatives Containing Only Halogen Substituents And Their Salts: Search List of Indian ITC HS Code and HS classification System Code, Harmonised System product code, Exim Codes Lookup and HS Code Finder. Inlcudes Harmonized Tariff Schedule A plot of % adsorption of phenol versus weight of activated carbon was drawn and it was found from the Fig. 4.28 that 2g of activated carbon was fixed as optimum carbon dosage. Time Dependence on Adsorption of Phenol: The amount of phenol adsorbed by carbon was found to vary with different time intervals The following waste classes may apply: U080 Dichloromethane; D026, Cresol; U052 Cresol; U188 Phenol; D002 Corrosive hazardous waste; F001 Spent halogenated solvent used in degreasing; F002 Spent halogenated solvent, F004 Spent non-halogenated solvents. The user is responsible for determining the appropriate waste category at the time of disposal

Alcohol, phenol ,and ethersTCP Liquid Antiseptic Original - 100 ml | Online Pharmacy UKINNA SOLYANIKOVA | Doctor of Sciences | Belgorod State

Any person who intends to manufacture (including import) a new chemical substance for a non-exempt commercial purpose, or to manufacture or process a chemical substance in a non-exempt manner for a use that EPA has determined is a significant new use, is required by TSCA section 5 to provide EPA with a PMN, MCAN or SNUN, as appropriate, before. HS Code 2908, List of Halogenated, sulphonated, nitrated or nitrosated derivatives of phenols or phenol-alcohols, Free Search Indian HS Classification, Harmonised Codes, Hs Code India India importers of (standard description) - Acyclic hydrocarbons - Halogenated, sulphonated, nitrated or nitrosated derivatives of phenols or phenol-alcohols under HS Code 2908 Import data to China, France, China Peoples Rep., Chin, Japan, Germany, United Kingdom from Jnpt, Mumbai, Mumbai, Calcutta, Madras The 2013 Import and Export Market for Halogenated, Sulfonated, Nitrated, or Nitrosated Phenol or Phenol-Alcohol Derivatives in Japan: International, Icon Group: Amazon.sg: Book Phenols and cresols are much weaker as acids than common carboxylic acids (phenol has pKa = 9.88). These materials are incompatible with strong reducing agents such as hydrides, nitrides, alkali metals, and inorganic sulfides. Flammable gas (H2) is often generated, and the heat of the reaction may ignite the gas