Stack effectThe stack effect or chimney effect is the movement of air into and out of buildings through unsealed openings, chimneys, flue-gas stacks, or other purposefully designed openings or containers, resulting from air buoyancy. Buoyancy occurs due to a difference in indoor-to-outdoor air density resulting from temperature and moisture differences. The result is either a positive or negative buoyancy force.
ChimneyA chimney is an architectural ventilation structure made of masonry, clay or metal that isolates hot toxic exhaust gases or smoke produced by a boiler, stove, furnace, incinerator, or fireplace from human living areas. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the stack, or chimney effect. The space inside a chimney is called the flue.
Air pollutionPresence of dangerous substances in the air
CombustionCombustion, or burning, is a high-temperature exothermicredoxchemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, because a flame is only visible when substances undergoing combustion vaporize, but when it does, a flame is a characteristic indicator of the reaction.
Power stationA power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Power stations are generally connected to an electrical grid. Many power stations contain one or more generators, rotating machines that convert mechanical power into three-phase electric power. The relative motion between a magnetic field and a conductor creates an electric current.
Flue gasFlue gas is the gas exiting to the atmosphere via a flue, which is a pipe or channel for conveying exhaust gases, as from a fireplace, oven, furnace, boiler or steam generator. It often refers to the exhaust gas of combustion at power plants. Technology is available to remove pollutants from flue gas at power plants. Combustion of fossil fuels is a common source of flue gas.
Natural-gas processingNatural-gas processing is a range of industrial processes designed to purify raw natural gas by removing contaminants such as solids, water, carbon dioxide (CO2), hydrogen sulfide (H2S), mercury and higher molecular mass hydrocarbons (condensate) to produce pipeline quality dry natural gas for pipeline distribution and final use. Some of the substances which contaminate natural gas have economic value and are further processed or sold.
Carbon monoxidePoisonous gas consisting of carbon and oxygenmodel of carbon monoxideNames IUPAC nameCarbon monoxideOther names Carbonic oxide gasCarbon protoxideOxide of carbonProtoxide of carbonCarbonous oxideCarbonous acid gasCarbon(II) oxideBreath of carbonOxygenated carbonCarbateCarbonylWater gasHydrocarbon gasFuel gasRauchgasCarbonic inflammable airHeavy inflammable airWhite dampFire DampPowder GasIlluminating gasDowson gasMond gasPower gasProducer gasBlast furnace gasCoal gasPhlogistonCar gasIdentifiers CAS Number630-08-03D model (JSmol)Interactive imageBeilstein Reference3587264 ChEBICHEBI:17245ChEMBLChEMBL1231840ChemSpider275ECHA InfoCard100.010.118EC Number211-128-3Gmelin Reference421 KEGGD09706MeSHCarbon+monoxidePubChemCID281RTECS numberFG3500000UNII7U1EE4V452UN number1016 CompTox Dashboard(EPA)DTXSID5027273InChIInChI=1S/CO/c1-2Key: UGFAIRIUMAVXCW-UHFFFAOYSA-NInChI=1/CO/c1-2Key: UGFAIRIUMAVXCW-UHFFFAOYATSMILES[C-]#[O+]Properties Chemical formulaCOMolar mass28.010 g·mol Appearance Colorless OdorOdorless Density789 kg/m, liquid1.250 kg/m at 0 °C, 1 atm1.145 kg/m at 25 °C, 1 atmMelting point−205.02 °C (−337.04 °F; 68.13 K) Boiling point−191.5 °C (−312.7 °F; 81.6 K) Solubility in water27.6 mg/L (25 °C) Solubilitysoluble in chloroform, acetic acid, ethyl acetate, ethanol, ammonium hydroxide, benzeneHenry's lawconstant (kH)1.04 atm·m/mol Magnetic susceptibility (χ)−9.8·10 cm/mol Refractive index (nD)1.0003364 Dipole moment0.122 DThermochemistry Heat capacity(C)29.1 J/(K·mol) Std molarentropy(S298)197.7 J/(K·mol) Std enthalpy offormation(ΔfH298)−110.5 kJ/mol Std enthalpy ofcombustion(ΔcH298)−283.0 kJ/mol Pharmacology ATC codeV04CX08 (WHO) Hazards Occupational safety and health (OHS/OSH): Main hazardsPoisonous by inhalationGHS labelling: PictogramsSignal wordDangerHazard statementsH220, H331, H360, H372, H420Precautionary statementsP201, P202, P210, P251, P260, P264, P270, P281, P304+P340, P308+P313, P311, P314, P321, P377, P381, P403, P403+P233, P405, P501NFPA 704 (fire diamond) 340Flash point−191 °C (−311.8 °F; 82.1 K) Autoignitiontemperature609 °C (1,128 °F; 882 K) Explosive limits12.5–74.2% Lethal dose or concentration (LD, LC): LC50 (median concentration)8636 ppm (rat, 15 min)5207 ppm (rat, 30 min)1784 ppm (rat, 4 h)2414 ppm (mouse, 4 h)5647 ppm (guinea pig, 4 h)LCLo (lowest published)4000 ppm (human, 30 min)5000 ppm (human, 5 min)NIOSH (US health exposure limits): PEL (Permissible)TWA 50 ppm (55 mg/m) REL (Recommended)TWA 35 ppm (40 mg/m)C 200 ppm (229 mg/m)IDLH (Immediate danger)1200 ppm Safety data sheet (SDS) ICSC 0023Related compounds Other anionsCarbon monosulfideOther cationsSilicon monoxideGermanium monoxideTin(II) oxideLead(II) oxideRelated carbon oxidesCarbon dioxideCarbon suboxideOxocarbonsSupplementary data page Carbon monoxide (data page)Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).Y verify ( ?)
Carbon dioxideCarbon-oxygen gasNames IUPAC nameCarbon dioxideOther names Carbonic acid gasCarbonic anhydrideCarbonic dioxideCarbonic oxideCarbon(IV) oxideMethanedioneR-744 (refrigerant)R744 (refrigerant alternative spelling)Dry ice (solid phase)Identifiers CAS Number124-38-93D model (JSmol)Interactive imageInteractive imageBeilstein Reference1900390 ChEBICHEBI:16526ChEMBLChEMBL1231871ChemSpider274ECHA InfoCard100.004.271EC Number204-696-9E numberE290 (preservatives)Gmelin Reference989 KEGGD00004MeSHCarbon+dioxidePubChemCID280RTECS numberFF6400000UNII142M471B3JUN number1013 (gas), 1845 (solid) CompTox Dashboard(EPA)DTXSID4027028InChIInChI=1S/CO2/c2-1-3Key: CURLTUGMZLYLDI-UHFFFAOYSA-NInChI=1/CO2/c2-1-3Key: CURLTUGMZLYLDI-UHFFFAOYAOSMILESO=C=OC(=O)=OProperties Chemical formulaCO2Molar mass44.009 g·mol Appearance Colorless gas OdorLow concentrations: noneHigh concentrations: sharp; acidicDensity1562 kg/m (solid at 1 atm (100 kPa) and −78.5 °C (−109.3 °F))1101 kg/m (liquid at saturation −37 °C (−35 °F))1.977 kg/m (gas at 1 atm (100 kPa) and 0 °C (32 °F))Critical point (T, P) 304.128(15) K (30.978(15) °C), 7.3773(30) MPa (72.808(30) atm) Sublimationconditions194.6855(30) K (−78.4645(30) °C) at 1 atm (0.101325 MPa) Solubility in water1.45 g/L at 25 °C (77 °F), 100 kPa (0.99 atm) Vapor pressure5.7292(30) MPa, 56.54(30) atm (20 °C (293.15 K)) Acidity (pKa) Carbonic acid:pKa1 = 3.6pKa1(apparent) = 6.35pKa2 = 10.33 Magnetic susceptibility (χ)−20.5·10 cm/mol Thermal conductivity0.01662 W·m·K (300 K (27 °C; 80 °F)) Refractive index (nD)1.00045 Viscosity14.90 μPa·s at 25 °C (298 K)70 μPa·s at −78.5 °C (194.7 K)Dipole moment0 D Structure Crystal structureTrigonal Point groupD∞hMolecular shapeLinearThermochemistry Heat capacity(C)37.135 J/(K·mol) Std molarentropy(S298)214 J·mol·K Std enthalpy offormation(ΔfH298)−393.5 kJ·mol Pharmacology ATC codeV03AN02 (WHO) Hazards GHS labelling: PictogramsSignal wordWarningHazard statementsH280, H281Precautionary statementsP282, P336+P317, P403, P410+P403NFPA 704 (fire diamond) 200SALethal dose or concentration (LD, LC): LCLo (lowest published)90,000 ppm (162,000 mg/m) (human, 5 min) NIOSH (US health exposure limits): PEL (Permissible)TWA 5000 ppm (9000 mg/m) REL (Recommended)TWA 5000 ppm (9000 mg/m), ST 30,000 ppm (54,000 mg/m) IDLH (Immediate danger)40,000 ppm (72,000 mg/m) Safety data sheet (SDS) Sigma-AldrichRelated compounds Other anionsCarbon disulfideCarbon diselenideCarbon ditellurideOther cationsSilicon dioxideGermanium dioxideTin dioxideLead dioxideTitanium dioxideZirconium dioxideHafnium dioxideCerium dioxideThorium dioxideRelated carbonoxidesSee OxocarbonRelated compoundsCarbonic acidCarbonyl sulfideCarbonyl selenideSupplementary data page Carbon dioxide (data page)Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).N verify ( ?)
NitrogenChemical element with atomic number 7 (N)–↑N↓Pcarbon ← nitrogen → oxygen
OxygenChemical element with atomic number 8 (O)–↑O↓Snitrogen ← oxygen → fluorine
NOxIn atmospheric chemistry, NOx is shorthand for nitric oxide (NO) and nitrogen dioxide (NO2), the nitrogen oxides that are most relevant for air pollution. These gases contribute to the formation of smog and acid rain, as well as affecting tropospheric ozone. NOx gases are usually produced from the reaction between nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as in car engines.
Particulate matterMicroscopic solid or liquid matter suspended in the Earth's atmospherePM2.5 and PM10 compared with a human hair in a graphic from the Environmental Protection Agency*As an Amazon Associate I earn from qualifying purchases.