Carl Scheele, masanin kimiyar Sweden, da Daniel Rutherford, masanin ilmin halittu na Scotland, sun gano nitrogen daban a 1772. Reverend Cavendish da Lavoisier suma sun sami nitrogen da kansu a kusan lokaci guda. Lavoisier ya fara gane Nitrogen a matsayin wani sinadari, wanda ya sanya masa suna "azo", ma'ana "marasa rai". Chaptal mai suna element nitrogen a 1790. Sunan ya samo asali ne daga kalmar Helenanci "nitre" (nitrate dauke da nitrogen a cikin nitrate).
Tushen Nitrogen
Nitrogen shine sinadari na 30 mafi yawa a duniya. Idan aka yi la'akari da cewa nitrogen yana da kashi 4/5 na ƙarar yanayi, ko fiye da 78%, muna da kusan ƙarancin nitrogen a gare mu. Nitrogen kuma ya wanzu a cikin nau'in nitrates a cikin ma'adanai daban-daban, irin su Chilean saltpeter (sodium nitrate), saltpeter ko nitre (potassium nitrate), da ma'adanai masu dauke da ammonium salts. Nitrogen yana kasancewa a cikin hadaddun kwayoyin halitta masu yawa, gami da sunadarai da amino acid da ke cikin dukkan halittu masu rai.
Kaddarorin jiki
Nitrogen N2 gas ne mara launi, mara ɗanɗano, kuma mara wari a cikin ɗaki, kuma yawanci ba mai guba bane. Yawan iskar gas a ƙarƙashin daidaitattun yanayi shine 1.25g/L. Nitrogen yana da kashi 78.12% na jimlar yanayi (ƙarashin juzu'i) kuma shine babban ɓangaren iska. Akwai kusan tan tiriliyan 400 na iskar gas a sararin samaniya.
Karkashin daidaitaccen yanayin yanayi, lokacin da aka sanyaya zuwa -195.8 ℃, ya zama ruwa mara launi. Lokacin da aka sanyaya zuwa -209.86 ℃, nitrogen ruwa ya zama ƙaƙƙarfan dusar ƙanƙara.
Nitrogen ba ya ƙonewa kuma ana ɗaukarsa iskar iskar iskar shaƙa (watau shaƙar nitrogen mai tsafta yana hana jikin ɗan adam iskar oxygen). Nitrogen yana da ƙarancin narkewa a cikin ruwa. A 283K, juzu'i ɗaya na ruwa zai iya narkar da kusan 0.02 juzu'i na N2.
Abubuwan sinadaran
Nitrogen yana da kyawawan kaddarorin sinadarai. Yana da wuya a yi mu'amala da wasu abubuwa a cikin ɗaki, amma yana iya yin canje-canjen sinadarai tare da wasu abubuwa a ƙarƙashin yanayin zafi da ƙarfin kuzari, kuma ana iya amfani da su don samar da sabbin abubuwa masu amfani ga ɗan adam.
Tsarin kwayoyin halitta na kwayoyin halitta na nitrogen shine KK σs2 σs * 2 σp2 σp * 2 πp2. Biyu uku na electrons suna ba da gudummawa ga haɗin gwiwa, wato, π bond biyu da σ bond ɗaya suna samuwa. Babu wata gudummawa ga haɗin gwiwa, kuma haɗin gwiwa da ƙarfin haɗin gwiwa kusan an biya su, kuma suna daidai da nau'ikan nau'ikan lantarki guda ɗaya. Tunda akwai haɗin N≡N sau uku a cikin kwayoyin N2, kwayoyin N2 yana da kwanciyar hankali sosai, kuma yana ɗaukar 941.69 kJ/mol na makamashi don lalata shi zuwa kwayoyin halitta. Kwayoyin N2 shine mafi kwanciyar hankali daga cikin kwayoyin diatomic da aka sani, kuma nauyin kwayoyin halitta na nitrogen shine 28. Bugu da ƙari, nitrogen ba shi da sauƙi don ƙonewa kuma baya goyan bayan konewa.
Hanyar gwaji
Sanya sandar Mg mai ƙonewa a cikin kwalbar tattara iskar gas da ke cike da nitrogen, kuma mashaya Mg zai ci gaba da ƙonewa. Cire sauran ash (kadan rawaya foda Mg3N2), ƙara ruwa kaɗan, sannan a samar da iskar gas (ammonia) wanda ke juya rigar ja litmus takarda blue. Ma'anar amsawa: 3Mg + N2 = kunnawa = Mg3N2 (magnesium nitride); Mg3N2 + 6H2O = 3Mg (OH) 2 + 2NH3↑
Halayen haɗin gwiwa da tsarin valence bond na nitrogen
Saboda abu guda N2 yana da matuƙar karko a ƙarƙashin yanayin al'ada, sau da yawa mutane suna kuskuren gaskata cewa nitrogen wani sinadari ne mara aiki. A gaskiya ma, akasin haka, sinadarin nitrogen yana da babban aikin sinadarai. Electronegativity na N (3.04) shine na biyu kawai zuwa F da O, yana nuna cewa yana iya samar da alaƙa mai ƙarfi tare da wasu abubuwa. Bugu da kari, kwanciyar hankali na kwayoyin halitta guda N2 kawai yana nuna ayyukan N atom. Matsalar ita ce har yanzu mutane ba su sami mafi kyawun yanayin kunna kwayoyin N2 a yanayin zafi da matsa lamba ba. Amma a yanayi, wasu kwayoyin cuta a kan nodules na shuka zasu iya canza N2 a cikin iska zuwa mahadi na nitrogen a karkashin yanayin rashin ƙarfi a yanayin zafi da matsa lamba, kuma suna amfani da su a matsayin taki don haɓaka amfanin gona.
Sabili da haka, nazarin gyare-gyaren nitrogen ya kasance wani muhimmin batu na bincike na kimiyya. Saboda haka, ya zama dole a gare mu mu fahimci halaye na haɗin gwiwa da tsarin valence bond na nitrogen daki-daki.
Nau'in Bond
Tsarin valence electron Layer na N atom shine 2s2p3, wato, akwai electrons guda 3 da nau'i-nau'i na lantarki guda biyu. Dangane da wannan, lokacin ƙirƙirar mahadi, ana iya samar da nau'ikan haɗin gwiwa guda uku masu zuwa:
1. Samar da ionic bonds 2. Samar da haɗin kai 3. Samar da haɗin kai.
1. Samar da igiyoyin ionic
N atoms suna da babban ƙarfin lantarki (3.04). Lokacin da suka samar da nitrides binary tare da karafa tare da ƙananan electronegativity, irin su Li (electronegativity 0.98), Ca (electronegativity 1.00), da Mg (electronegativity 1.31), za su iya samun 3 electrons kuma su samar da N3- ions. N2+ 6 Li == 2 Li3N N2+ 3 Ca == Ca3N2 N2+ 3 Mg = ignite= Mg3N2 N3- ions suna da mafi girman cajin mara kyau da radius mafi girma (171pm). Za su kasance da ƙarfi mai ƙarfi lokacin da suka haɗu da kwayoyin ruwa. Sabili da haka, mahadi na ionic na iya zama kawai a cikin busassun yanayi, kuma ba za a sami ions mai ruwa na N3- ba.
2. Samuwar covalent bond
Lokacin da N atoms suka samar da mahadi tare da waɗanda ba ƙarfe ba tare da mafi girman electronegativity, ana samun haɗin haɗin haɗin gwiwa masu zuwa:
⑴N atoms suna ɗaukar yanayin sp3 hybridization, samar da covalent bond guda uku, riƙe nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nau'i na lantarki, kuma tsarin kwayoyin halitta pyramidal trigonal, kamar NH3, NF3, NCl3, da sauransu. tetrahedron na yau da kullun, kamar NH4+ ions.
⑵N atoms suna ɗaukar yanayin haɓakawar sp2, suna samar da haɗin kai guda biyu da haɗin gwiwa ɗaya, kuma suna riƙe nau'ikan nau'ikan lantarki guda biyu, kuma ƙirar ƙwayoyin cuta tana angular, kamar Cl-N=O. (N atom yana samar da haɗin σ da kuma π bond tare da Cl atom, kuma nau'i-nau'i na electron guda biyu akan N atom suna yin triangular na kwayoyin halitta. NO3-ion. A cikin kwayoyin nitric acid, N atom yana samar da haɗin σ guda uku tare da zarra O guda uku, da kuma nau'ikan electrons a kan π orbital ɗinsa da guda π electrons na O atoms guda biyu suna samar da haɗin tsakiya huɗu na electron π. A cikin nitrate ion, an samar da babban haɗin lantarki na tsakiya shida na tsakiya huɗu tsakanin O atoms uku da tsakiyar N atom. Wannan tsarin yana sanya alamar oxidation lambar N atom a cikin nitric acid +5. Saboda kasancewar manyan π bonds, nitrate yana da ƙarfi sosai a ƙarƙashin yanayin al'ada. ⑶N zarra ya ɗauki sp hybridization don samar da covalent sau uku bond kuma yana riƙe da nau'i-nau'i na lantarki guda biyu. Tsarin kwayoyin halitta yana da layi, kamar tsarin N atom a cikin kwayoyin N2 da CN-.
3. Samar da haɗin kai
Lokacin da ƙwayoyin nitrogen suka samar da abubuwa masu sauƙi ko mahadi, galibi suna riƙe nau'ikan nau'ikan lantarki guda ɗaya, don haka irin waɗannan abubuwa masu sauƙi ko mahadi suna iya aiki azaman masu ba da gudummawar nau'ikan lantarki don daidaitawa zuwa ions na ƙarfe. Misali, [Cu(NH3)4]2+ ko [Tu(NH2)5]7, da sauransu.
Oxidation jihar-Gibbs zanen makamashi kyauta
Hakanan za'a iya gani daga tsarin oxidation state-Gibbs free makamashi zane na nitrogen cewa, ban da NH4 ions, N2 kwayoyin tare da oxidation lamba na 0 ne a mafi ƙasƙanci wuri na kwana a cikin zane, wanda ya nuna cewa N2 ne thermodynamically. barga dangane da mahadi na nitrogen tare da wasu lambobi oxidation.
Ma'auni na daban-daban na nitrogen mahadi tare da hadawan abu da iskar shaka lambobi tsakanin 0 da +5 duk suna sama da layin da ke haɗa maki biyu HNO3 da N2 (layin dige a cikin zane), don haka waɗannan mahadi ba su da ƙarfi kuma suna da haɗari ga halayen rashin daidaituwa. Kadai a cikin zane mai ƙarancin ƙima fiye da kwayoyin N2 shine NH4+ ion. [1] Daga tsarin oxidation state-Gibbs tsarin makamashi na kyauta na nitrogen da tsarin kwayoyin N2, ana iya ganin cewa N2 na farko baya aiki. Sai kawai a ƙarƙashin matsanancin zafin jiki, matsa lamba mai ƙarfi da kasancewar mai haɓakawa zai iya yin hulɗa tare da hydrogen don samar da ammonia: A ƙarƙashin yanayin fitarwa, nitrogen na iya haɗuwa da oxygen don samar da nitric oxide: N2 + O2 = fitarwa = 2NO Nitric oxide da sauri ya haɗu tare da oxygen zuwa samar da nitrogen dioxide 2NO+O2=2NO2 Nitrogen dioxide yana narkewa a cikin ruwa don samar da nitric acid, nitric oxide 3NO2+H2O=2HNO3+NO A cikin kasashen da suka ci gaba da karfin ruwa, an yi amfani da wannan dauki wajen samar da nitric acid. N2 yana amsawa da hydrogen don samar da ammonia: N2+3H2=== (alama mai juyawa) 2NH3 N2 yana amsawa da karafa tare da yuwuwar yuwuwar ionisation kuma wanda nitrides suna da ƙarfi mai ƙarfi don samar da ionic nitrides. Misali: N2 na iya amsawa kai tsaye da lithium na karfe a dakin da zafin jiki: 6 Li + N2=== 2 Li3N N2 yana amsawa da karafan alkaline earth Mg, Ca, Sr, Ba a yanayin zafi: 3 Ca + N2=== Ca3N2 N2 iya kawai amsa da boron da aluminum a yanayin zafi: 2 B + N2 === 2 BN (macromolecule compound) N2 gabaɗaya yana amsawa da silicon da sauran abubuwan rukuni a yanayin zafi sama da 1473K.
Kwayoyin nitrogen suna ba da gudummawar nau'i-nau'i na electrons guda uku don haɗawa, wato, samar da haɗin π biyu da haɗin σ ɗaya. Ba ya ba da gudummawa ga haɗin gwiwa, kuma haɗin gwiwa da ƙarfin haɗin gwiwa kusan an biya su, kuma sun yi daidai da nau'ikan nau'ikan lantarki guda ɗaya. Domin akwai N≡N sau uku a cikin kwayoyin N2, kwayoyin N2 yana da kwanciyar hankali sosai, kuma yana daukan 941.69kJ/mol na makamashi don lalata shi zuwa kwayoyin halitta. Kwayoyin N2 shine mafi kwanciyar hankali daga cikin kwayoyin diatomic da aka sani, kuma nauyin kwayoyin halitta na nitrogen shine 28. Bugu da ƙari, nitrogen ba shi da sauƙi don ƙonewa kuma baya goyan bayan konewa.
Lokacin aikawa: Yuli-23-2024
