Ammonia tshuaj - kev npaj thiab kev siv

Nitrogen (Nitrogen) muaj ob peb txuas rau lub hydrogenous (hydrogen), uas qhov tseem ceeb yog tseem ceeb ammonia. Nyob rau hauv lub laboratory nws yog npaj los ntawm cua sov ib tug sib tov ntawm ammonium tshuaj dawb nrog poov tshuaj hydroxide. Kom txog rau thaum lub caij puv 19 xyoo pua, lub Chilean deposit ntawm sodium nitrate twb xam tias yog qhov tsuas qhov chaw ntawm Nitrogen tebchaw. Tsaug rau kev tshawb fawb, chemists yog ob peb txoj kev atmospheric Nitrogen fixation twb npaj siab. Tus thawj ntawm cov yog cov cyanamide ammonia synthesis txheej txheem. Qhov no yog raws li nyob rau hauv cov cuab yeej ntawm nitrogen coupled rau calcium carbamide. Rau lub hom phiaj no, lub rhuab nitrogen yog dhau los ntawm cov calcium uas carbide:

N2 + CaC2 = CaCN2 + C

Cov li no tau CaCN2 (calcium cyanide) nitrate yog siv raws li chiv nyob rau hauv ua liaj ua teb. Nws yuav tsum tau hais tias cov kev kho mob ntawm no compound nrog chav rau ua ammonia:

CaCN2 + ZN20 = 2NH3 + CaC03

Ammonia ua rau acid thiab ib tug nitrate nitrogen chiv. Nyob rau hauv niaj hnub Science News for KIDS yog thoob plaws lwm txoj kev muab NH3 - nws synthesis ntawm Nitrogen thiab Hydrogen:

1/2 N +3/2 H2 = NH3

ammonia li tau yog hu ua hluavtaws. Muaj ammonia synthesis yog nqa tawm nyob rau xub ntiag ntawm ib lub hauv paus thiab thaum ib tug kub ntawm 500 degrees.

Ammonia - ib tug roj uas muaj ib tug pungent yam ntxwv tsw, nws yog sib zog dua cov pa. NH3 yuav tsum tsis txhob nqus tau cov pa rau ib ntev lub sij hawm, vim hais tias nws yog tshuaj lom. Cov pa roj yog tus yooj yim soluble nyob rau hauv H2O. Concentrated aqueous ammonia muaj 25% NH3.

Thaum txias (rau -79 ° C) tov ntawm aqueous ammonia yuav crystalline. Kev tshawb fawb tau qhia hais tias lub ntsiab loj ntawm NH3 nyob rau hauv lub aqueous tov yog nyob rau hauv daim ntawv ntawm hydrated molecules (NH3 · nH2O) thiab tsuas yog ib tug me me ib feem ntawm lub neej ammonia (hais txog 0.5%) reacted nrog dej:

NH3 + H2O = NH4 + + OH -

Alkaline cov tshuaj tiv thaiv ntawm ammonia kev daws teeb meem vim lub xub ntiag ntawm hydroxide ions. Feeb ammonia tshuaj xws li NH4OH. Lub alkalinity ntawm cov tshuaj los ntawm lub xub ntiag ntawm ib tug hydroxyl pab pawg neeg, uas yog tsim nyob rau raws li ib tug tshwm sim ntawm dissociation ntawm ammonium hydroxide.

Ammonia tshuaj yog suav tias yog tsis muaj zog los luj. Nyob rau hauv lub chaw soj nstuam tej zaum ammonia twb npaj los ntawm cua sov ammonium tshuaj dawb. Ammonia yog heev active tshuaj compound uas reacts nrog ntau yam, thaum uas qhia tsuas txo zog.

Ammonia Burns nrog rau oxygen hauv cov xub ntiag ntawm ib tug greenish-daj nplaim taws, thaum uas oxidized rau ib tug dawb Nitrogen. Thaum lub xub ntiag ntawm lub catalyst (platinum) · ammonia oxidation mus rau kom txog thaum ib tug Nitrogen oxide. Qhov no cov tshuaj tiv thaiv yog siv nyob rau hauv tus txheej txheem ntawm cov nitric acid. Nws yuav tsum tau hais tias feem ntau ntawm cov li tau ammonia yog siv rau zus tau tej cov nitrate chiv thiab nitric acid.

Thaum lub sij hawm evaporation ntawm -33,4 ° C kua NH3 los ntawm cov ib puag ncig absorbs ib tug ntau ntawm tshav kub, nws ua cua txias. Qhov no tej khoom vaj tse yog nws siv nyob rau hauv cov tub yees tshuab rau dag ice cia ntawm kev txawj ploj tuag khoom noj. Feem ntau cov kua ammonia yog siv nyob rau hauv kev tsim kho ntawm underground lug. Lub ammonia tshuaj no yog siv nyob rau hauv laboratory xyaum, cov tshuaj ua lag luam, tsev neeg cov khoom, thiab nyob rau hauv cov tshuaj.

ammonia tshuaj daim ntawv thov. Siv raws li txhais tau tias rau excitation thiab tshem tawm ntawm kev ua pa ntawm tus neeg mob los ntawm tsaus muag. Loj ntau ntawm NH3 yuav ua rau ua pa raug ntes. Tej zaum ammonia tshuaj yog siv raws li emetics (10 ncos ib 100 ml dej). Nco ntsoov hais tias qhov no kws npaj yuav tsis muaj ntaub ntawv topically nyob rau hauv lub xub ntiag ntawm daim tawv nqaij kab mob (eczema, dermatitis). Yog hais tias lom ammonia vapors cov kws kho mob muab cov tshuaj acetate, citrate, tartrate (tartaric acid) ntawm 1% concentration. Nyob rau hauv phais xyaum siv ammonia tshuaj (25 ml / 5 liter ntawm boiled, dej kub).