Yuav ua li cas yog nitrogen? Pawg nitrogen. nitrogen molecule

Cov uas tsis yog-metallic caij ntawm lub 15th pab pawg neeg [Va] Periodic Rooj - nitrogen atom 2 ntawm uas muab mus ua ib lub qauv - tsis muaj kob, ntxhiab thiab tasteless roj constituting ib tug loj ib feem ntawm lub ntiaj teb huab cua thiab cov uas yog ib feem ntawm tag nrho cov nyob yam.

Keeb kwm ntawm foundations

Nitrogen roj yog hais txog 4/5 ntawm lub ntiaj teb huab cua. Nws twb cais nyob rau hauv thaum ntxov Cua tshawb fawb. Nyob rau hauv 1772, Swedish Himik Karl Wilhelm Scheele thawj qhia hais tias xws li ib tug nitrogen. Raws li nws, cov huab cua yog ib tug sib tov ntawm ob gases, ib tug uas nws hu ua "hluav taws cua", uas yog los pab txhawb cov combustion, thiab lwm yam - .. "impure cua" vim hais tias nws tseem tom qab thawj zaug noj. Cov no yog cov pa thiab nitrogen. Nyob ib ncig ntawm tib lub sij hawm nitrogen tau muab cais tawm los ntawm lub Scottish botanist Daniel Rutherford, uas thawj luam tawm nws tshawb pom, raws li zoo raws li lub British chemist Henry Cavendish thiab lub British clergyman thiab paub txog Dzhozefom Pristli, uas muab qhia rau Scheele primacy ntawm lub foundations ntawm cov pa. Ntxiv cov kev tshawb fawb pom tau hais tias tshiab roj yog ib feem ntawm lub nitrate los yog poov tshuaj nitrate (KNO _3), thiab, raws li, nws lub npe hu ua ntawm ib tug nitrogen ( "muab yug saltpeter") los ntawm qhov Fabkis chemist Chaptal nyob rau hauv 1790 Nitrogen twb xub ntaus nqi mus rau tshuaj lom neeg ntsiab ntawm Lavoisier, uas nws piav txog lub luag hauj lwm ntawm cov pa nyob rau hauv combustion disproved lub phlogiston kev tshawb xav - nrov nyob rau hauv lub XVIII caug xyoo. misconception combustion. Lub cev tsis ntawm no tshuaj caij los pab txhawb lub neej (Greek ζωή) yog vim li cas hais tias Lavoisier npe nitrogen roj.

Lub rov tshwm sim thiab kis

Yuav ua li cas yog nitrogen? Raws li cov nplua mais ntawm cov tshuaj hais, nws ranked sixth. Lub ntiaj teb huab cua rau 75,51% los ntawm qhov nyhav thiab 78,09% los ntawm volume yog muaj li ntawm lub caij thiab nws yog ib tug loj qhov twg los rau hauv lub lag luam. Cov huab cua kuj muaj ib tug me me npaum li cas ntawm ammonia thiab ammonium ntsev, raws li zoo raws li nitrogen oxides thiab nitric acid, tsim thaum lub sij hawm thunderstorms thiab nyob rau hauv internal combustion xyaw. Dawb nitrogen yog nyob rau hauv ntau meteorites, volcanic thiab kuv roj thiab ib co mineral springs, lub hnub, lub hnub qub thiab nebulae.

Nitrogen yog tseem pom nyob rau hauv cov mineral deposits ntawm poov tshuaj thiab sodium nitrate, tab sis kom tau raws li tib neeg xav tau kev pab txaus. Lwm cov ntaub ntawv uas nplua nuj nyob rau hauv no lub caij yog guano, uas muaj peev xwm yuav nrhiav tau nyob rau hauv lub caverns, qhov twg ntau ntau puav, los yog lub qhuav qhov chaw frequented los ntawm cov noog. Tsis tas li ntawd, nitrogen yog muaj nyob rau hauv cov nag thiab av nyob rau hauv daim ntawv ntawm ammonia thiab ammonium ntsev, thiab nyob rau hauv hiav txwv dej nyob rau hauv daim ntawv ntawm ammonium ions (NH ₄ ^+), nitrite (TSIS MUAJ ₂ ^-) thiab nitrate (TSIS MUAJ ₃ ^-). Qhov nruab nrab yog hais txog 16% ntawm complex organic tebchaw xws li cov nqaijrog, yog tam sim no nyob rau hauv tag nrho cov uas muaj sia nyob. Lub ntuj cov ntsiab lus nyob rau hauv lub ntiaj teb ua kiav txhab yog 0.3 qhov chaw los ntawm 1000 tauj loj heev nyob rau hauv qhov chaw - los ntawm 3 mus rau 7 atoms ib silicon atom.

Qhov loj tshaj plaws uas ua lub teb chaws ntawm nitrogen (raws li ammonia) nyob rau hauv thaum pib ntawm lub XXI xyoo pua, twb Is Nrias teb, Zog ntawm Guj kuj, hauv lub tebchaws United States, Trinidad thiab Tobago, Ukraine.

Coj mus muag ntau lawm thiab kev siv

Muaj ntau lawm ntawm nitrogen yog raws li nyob rau hauv ib tug fractional distillation ntawm liquefied cua. Nws kub kub yog sib npaug zos rau -195,8 ° C, 13 ° C qis dua cov pa, uas yog li cais. Nitrogen kuj yuav ua rau ib tug loj scale los ntawm cov combustion ntawm carbon los yog hydrocarbons nyob rau hauv cov huab cua thiab nkauj nraug lub resulting carbon dioxide thiab dej los ntawm residual nitrogen. Nyob rau hauv me me scale ntshiab nitrogen yog ua los ntawm cua sov rau cov azide barium kav ywm (N _{3) 2.} Kuaj cov tshuaj tiv thaiv xws li cua sov ib tug tov ntawm ammonium nitrite (NH ₄ TSIS _2), cov oxidation ntawm ammonia nrog ib tug aqueous bromine tshuaj los yog nrog rhuab tooj liab oxide :

• NH ₄ ^{+ +} TSIS ₂ ^- → N ₂ + 2H ₂ O.
• 8NH ₃ + 3Br ₂ → N ₂ + 6NH ₄ ^{+ +} 6Br ^-.
• 2NH ₃ + 3CuO → N ₂ + 3H ₂ O + 3Cu.

Elemental nitrogen tej zaum yuav siv tau raws li ib tug inert cua rau tshua tau cais tawm ntawm cov pa thiab dej. Yog siv thiab kua nitrogen. Hydrogen, methane, carbon monoxide, oxygen, fluorine, thiab - qhov tsuas tshuaj uas, thaum boiling point ntawm nitrogen yog tsis nyob rau hauv ib tug khoom crystalline lub xeev.

Nyob rau hauv lub tshuaj kev lag luam, qhov no tshuaj caij yog siv los mus tiv thaiv oxidation los yog lwm yam ua rau zaubmov lwj, raws li ib tug inert diluent, ib tug reactive roj kom tshem tawm cov tshav kub los yog tshuaj, raws li zoo raws li ib tug tua hluav taws los yog tawg inhibitor. Nyob rau hauv cov zaub mov kev lag luam, nitrogen pa roj yog siv los mus tiv thaiv ua rau zaubmov lwj, thiab cov kua - rau freeze-qhuav thiab cua txias tshuab. Nyob rau hauv qhov hluav taws xob kev lag luam roj tiv thaiv oxidation thiab lwm yam tshuaj tshua, pressurizes lub cable sheath thiab tiv thaiv lub motors. Nyob rau hauv metallurgy, nitrogen yog siv nyob rau hauv vuam thiab brazing, tiv thaiv oxidation, carburization, thiab decarburization. Raws li cov tsaug zog roj nws yog siv nyob rau hauv qhuav ntawm ntxeem tau roj hmab, uas thiab cov elastomers, nws ua hauj lwm pab raws li ib tug propellant nyob rau hauv aerosol poom, thiab kuj tsim ib tug siab nyob rau hauv cov kua roj dav hlau. Nyob rau hauv cov tshuaj, ceev ceev freezing nrog kua nitrogen yog siv los khaws cov ntshav, hloov hlwb pob txha, cov nqaij mos, cov kab mob thiab cov phev. Nws tau pom daim ntawv thov nyob rau hauv cryogenic kev tshawb fawb.

kev sib txuas

Feem ntau ntawm cov nitrogen siv nyob rau hauv qhov siv thiab ua cov tshuaj tebchaw. Lub triple daim ntawv cog lus nruab nrab ntawm cov atoms ntawm lub caij yog li ntawd muaj zog (226 Kcal ib lub tias ntawm ob zaug siab tshaj uas ntawm molecular hydrogen), uas nitrogen molecule tsis yog nkag mus rau mus rau lwm lub tebchaw.

Lub ntsiab muaj txoj kev fixation caij yog Haber-Bosch txheej txheem rau cov synthesis ntawm ammonia tsim thaum lub sij hawm lub ntiaj teb no ua tsov ua rog II, lub teb chaws Yelemees rau txo dependence rau lub Chilean nitrate. Nws muaj xws li ncaj qha synthesis ntawm NH ₃ - tsis muaj kob roj nrog ib tug pungent, khaus tsw - ncaj qha los ntawm nws cov ntsiab.

Feem ntau ntawm cov ammonia yog hloov dua siab tshiab rau nitric acid (HNO _3), thiab nitrates - ntsev thiab esters ntawm nitric acid, dej qab zib tshauv (Na ₂ CO _3), hydrazine (N ₂ H ₄₎ - tsis muaj kob kua siv raws li ib tug propellant, thiab nyob rau hauv ntau industrial dab.

Nitric acid yog lub loj coj mus muag tshuaj compound ntawm lub caij. Tsis muaj kob, mas corrosive kua yog siv nyob rau hauv qhuav ntawm chiv, dyes, tshuaj thiab tawg. Ammonium nitrate (NH ₄ TSIS ₃₎ - ntsev ntawm ammonia thiab nitric acid - yog lub feem ntau nitrogen chiv tivthaiv.

Pa + nitrogen

C ntaub ntawv ib tug series ntawm cov pa, nitrogen oxides, r. H. Nitrous oxide (N ₂ O), nyob rau hauv uas nws yog sib npaug zos rau cov valence ntawm +1 oxide (TSIS YOG) (+2) thiab dioxide (TSIS MUAJ ₂₎ (4). Muaj ntau heev volatile nitrogen oxides; lawv yog cov tseem ceeb qhov chaw ntawm cov pa phem nyob rau hauv cov cua. Nitrous oxide, kuj hu ua luag roj, yog tej zaum kuj siv raws li ib tug ua kom loog. Thaum nqus tau cov pa, nws ua me me hysteria. Nitric oxide reacts sai heev nrog cov pa mus ua ib lub xim av dioxide intermediate khoom nyob rau hauv lub zus tau tej cov nitric acid thiab ib tug muaj zog oxidant nyob rau hauv cov tshuaj dab thiab propellant.

Kuj siv yog ib co nitrides tsim los ntawm cov hlau nrog ib tug nitrogen compound ntawm txhawb kub. Nitrides ntawm boron, titanium, zirconium thiab tantalum muaj kev tshwj xeeb daim ntawv thov. Ib tug crystalline daim ntawv ntawm boron nitride (BN), piv txwv li, yog tsis inferior mus pob zeb diamond nyob rau hauv hardness thiab oxidized phem yog li ntawd siv raws li high-abrasive.

Inorganic cyanides muaj CN pab pawg neeg ^-. Hydrogen cyanide los yog hydrocyanic acid HCN, yog ib co neeg tsis mloog thiab tsis tshua muaj tshuaj lom roj uas yog siv rau fumigation ntau ore nyob rau hauv lwm yam kev ua. Cyanogen (CN) ₂ yog siv raws li ib tug tshuaj intermediate thiab rau fumigation.

Azides yog tebchaw uas muaj ib pab pawg neeg ntawm peb nitrogen atoms -N _3. Feem ntau ntawm lawv yog tsis ruaj tsis khov thiab rhiab heev rau shocks. Ib txhia ntawm lawv, xws li cov hlau lead azide, Pb (N _{3) 2,} siv nyob rau hauv detonators thiab primers. Azides, zoo li halogens, nkag koom tau nrog lwm yam yuav tsim ib tug plurality ntawm tebchaw.

Nitrogen yog ib feem ntawm ob peb txhiab ntawm cov organic tebchaw. Feem ntau ntawm lawv yog derived ntawm ammonia, hydrogen cyanide, cyanogen, cov pa roj nitrous los yog nitric acid. Amines, amino acids, amides, piv txwv li, muab tau los ntawm ammonia los yog ib tug ze ze muaj feem xyuam rau nws. Nitroglycerine thiab nitrocellulose - nitric esters. Nitrite twb npaj los ntawm cov pa roj nitrous acid (HNO _2). Purines thiab alkaloids yog heterocyclic tebchaw nyob rau hauv uas lub nitrogen xyoo ib los yog ntau tshaj carbon atoms.

Properties thiab tshua

Yuav ua li cas yog nitrogen? Nws yog ib tug tsis muaj kob, ntxhiab pa uas condenses ntawm -195,8 ° C, tsis muaj kob, tsis tshua muaj viscosity kua. Caij tshwm sim nyob rau hauv daim ntawv ntawm N ₂ molecules, uas muaj tuaj nyob rau hauv daim ntawv: N ::: N:, nyob rau hauv uas lub daim ntawv cog lus lub zog sib npaug zos rau 226 Kcal ib tus nas, zaum ob tsuas yog mus carbon monoxide (256 kilocalories ib tus nas). Vim li no, qhov ua kom lub zog ntawm molecular nitrogen yog heev siab heev, thiaj li nyob rau hauv ib txwm tej yam kev mob rau lub caij yog tus inert. Tsis tas li ntawd, mas ruaj khov nitrogen molecule heev muaj txhawb rau thermodynamic khov ntawm ntau nitrogen tebchaw, nyob rau hauv uas zoo sib xws, txawm hais tias muaj zog txaus, tab sis ua tsis tau zoo kev sib raug zoo molecular nitrogen.

Kuj ntev los no, thiab muaj peev xwm ntawm cov nitrogen molecules twb poob nthav sab pab raws li ligands rau txoj tebchaw. Cov soj ntsuam hais tias ib co ntsiab ntawm ruthenium ceg yuav nqus atmospheric nitrogen coj mus rau dab tsi tej zaum sai sai nrhiav tau ib tug yooj yim thiab txoj kev zoo ntawm kev kho lub caij.

Active nitrogen yuav tsum tau los ntawm xeem dhau tsis tshua muaj siab roj los ntawm high-voltage fais tawm. Cov khoom no amber thiab ntau npaum li cas nkag reacts tshaj molecular, atomic hydrogen, sulfur, phosphorous thiab ntau yam co, thiab kuj yog muaj peev xwm sawv ntawm decomposing TSIS rau N ₂ thiab O _2.

Ib tug Hanpaku to taub vim li cas yog nitrogen, yuav ua li cas vim nws siv hluav taws xob qauv uas muaj rau hauv daim 1s 2s ^{2 2 3} 2p. Tsib lwm electron zoo li me ntsis tshuaj ntsuam tus nqi, uas ua nyob rau hauv zoo nuclear xwb muaj nyob rau hauv lub cheeb tsam ntawm lub covalent voos kheej-kheej. Nitrogen atoms yog kuj me me thiab muaj lub siab electronegativity, nyob nruab nrab ntawm cov pa roj carbon thiab oxygen. E configuration nrog peb sab nraud ib nrab-orbitals, enabling tsim peb covalent bonds. Yog li ntawd, lub nitrogen atom yuav tsum muaj tsis tshua muaj neeg siab reactivity, txoj kev nrog lwm cov ntsiab ruaj khov binary tebchaw, tshwj xeeb tshaj yog thaum lwm lub caij yog tshuam txawv electronegativity, imparts tseem ceeb polarity sib txuas. Thaum lwm lub caij electronegativity qis polarity txuas mus rau cov nitrogen atom ntawm ib nrab tsis zoo xwb, uas thiaj li los tso nws unshared electrons mus koom nyob rau hauv kev sib koom tes bonds. Thaum lwm lub caij ntau electronegative nitrogen ib nrab zoo xwb tshuam txwv pub thaj chaw ntawm lub molecule. Thaum uas tsis muaj polarity vim vim hais tias ntawm lub electronegativity sib npaug lwm lub caij, ntau yam kev sib txuas lus yeej tshaj ib. Yog hais tias lub atomic loj mismatch tsis pub tsim los ntawm ntau yam bonds uas tsim ib tug tib daim ntawv cog lus no yuav tsum tau kuj tsis muaj zog, thiab kev twb kev txuas yog tsis ruaj tsis khov.

analytical Science News for KIDS

Feem ntau cov feem pua ntawm cov nitrogen nyob rau hauv cov roj sib tov yuav tsum tau txiav txim los ntawm ntsuas nws cov ntim tom qab haum lwm Cheebtsam ntawm cov tshuaj reagents. Lub decomposition ntawm sulfuric acid nyob rau hauv lub xub ntiag ntawm mercury nitrate tawm nitric oxide, uas yuav tsum tau ntsuas raws li ib tug roj. Nitrogen yog liberated los ntawm organic tebchaw thaum lawv hlawv dua ib tooj liab oxide, thiab cov dawb nitrogen tej zaum yuav ntsuas raws li ib tug roj tom qab cov haum lwm combustion khoom. Ib tug zoo-paub Kjeldahl txoj kev rau kev txiav txim ntawm tshuaj xam tau tias yog no nyob rau hauv cov organic tebchaw muaj nyob rau hauv decomposing lub compound nrog concentrated sulfuric acid (optionally muaj mercury los yog nws oxide, thiab ntau yam ntsev). Yog li nitrogen yog hloov dua siab tshiab rau ammonium sulfate. Ntxiv sodium hydroxide tawm ammonia, uas yog sau los ntawm cov pa acid; lub residual nyiaj ntawm unreacted acid yog ces txiav txim los ntawm titration.

Lom thiab physiological tseem ceeb

Lub luag hauj lwm ntawm nitrogen nyob rau hauv lub nyob muaj teeb meem tuaj yuav qhia nws physiological kev ua si ntawm cov organic tebchaw. Feem ntau cov uas muaj sia nyob yuav tsis siv qhov no tshuaj caij nws tus kheej yuav tsum muaj kev nkag tau rau nws cov tebchaw. Yog li ntawd, lub nitrogen fixation yog qhov tseem ceeb. Nyob rau hauv cov xwm, qhov no tshwm sim raws li ib tug tshwm sim ntawm ob yooj yim dab. Ib tug yog cov nyhuv ntawm hluav taws xob lub zog mus rau lub ntuj kaaj quas lug, yog li ntawd nitrogen thiab cov pa molecules dissociate, uas free atoms tsim TSIS thiab TSIS MUAJ _2. Dioxide ces reacts nrog dej: 3NO ₂ + H ₂ O → 2HNO ₃ + TSIS.

HNO ₃ yog yaj thiab los rau ntiaj teb los ntawm cov nag nyob rau hauv daim ntawv ntawm cov tsis muaj zog cawv. Nws thiaj li acid yuav ib feem ntawm lub neej coj av nitrogen uas yog neutralized tsim nitrites thiab nitrates. Cov ntsiab lus ntawm N nyob rau hauv cultivated xau feem ntau zoo tu qab tso los ntawm fertilization muaj nitrates thiab ammonium ntsev. Saws tsiaj thiab nroj tsuag thiab lawv decomposition rov nitrogen compound mus rau hauv cov av thiab huab cua.

Lwm loj tej yam ntuj tso kho cov txheej txheem tseem ceeb heev kev ua si ntawm legumes. Vim symbiosis nrog cov kab mob, cov haiv neeg muaj peev xwm hloov atmospheric nitrogen ncaj qha mus rau hauv nws lub tebchaw. Ib txhia kab mob, xws li Azotobacter Chroococcum thiab Clostridium pasteurianum, yog tau txhim kho lawv tus kheej N.

cov roj nws tus kheej, ua inert, txawm, tsuas yog thaum lawv ua pa nyob rau hauv siab, thiab nws yog yaj nyob rau hauv cov ntshav thiab lwm yam kua nruab nrog cev ntawm ntau dua. Qhov no ua rau cov tshuaj ua hauj lwm, thiab yog hais tias lub siab yog txo heev sai sai, tshaj nitrogen yog tso tawm raws li roj npuas rau lwm qhov chaw ntawm lub cev. Qhov no yuav ua rau mob nyob rau hauv cov nqaij thiab pob qij txha, tsaus muag, ib nrab tuag tes tuag taw thiab tuag taus. Cov tsos mob no yog hu ua decompression kev mob kev nkeeg. Yog li ntawd, cov neeg uas yog yuam kom ua pa cov cua nyob rau hauv tej yam yuav tsum tau qeeb heev los txo lub siab mus rau ib tug ib txwm mus rau hauv lub dhau heev lawm nitrogen tawm los ntawm lub ntsws tsis muaj tus tsim ntawm bubbles. Ib tug zoo dua lwm txoj yog siv ib tug breathable sib tov ntawm cov pa thiab Helium. Helium yog tsawg npaum li cas soluble nyob rau hauv lub cev, thiab qhov uas yuav tau tsawg.

isotopes

Nitrogen tshwm sim raws li ob ruaj khov isotopes ¹⁴ N (99,63%) thiab ¹⁵ N (0,37%). Lawv yuav tsum tau sib cais los ntawm cov tshuaj pauv los yog los ntawm thermal diffusion. nitrogen loj nyob rau hauv daim ntawv ntawm cov khoom cua tej isotope yog nyob rau hauv ntau 10-13 thiab 16-24. Qhov tseem ruaj khov ib nrab-lub neej ntawm 10 feeb. Thawj artificially ntxias nuclear transmutation tau ua nyob rau hauv 1919 los ntawm cov British physicist Ernest Rutherford, uas bombarding nitrogen-14 alpha-hais tau nucleus-17 oxygen thiab protons.

zog

Thaum kawg sau cov yooj yim zog ntawm nitrogen:

• Atomic tooj: 7.
• Atomic luj ntawm nitrogen: 14,0067.
• Melting point: -209,86 ° C.
• Kub point: -195,8 ° C.
• Ceev (1 atm, 0 ° C): 1,2506 grams ntawm nitrogen rau ib liter.
• Pa oxidation lub xeev ntawm -3, +3, +5.
• Electron configuration: 1s 2s ^{2 2 3} 2p.