Sodium hydroxide: mis nyuj tov, lub zog thiab daim ntawv thov

Ib qho tseem ceeb tshuaj tebchaw tsim loj loj ob tog txhua xyoo alkali yog sodium hydroxide. Tej chaw nws yuav tsum tau txais vim lawv lub zog. Caustic dej qab zib, uas mis - NaOH, yog ntawm kuj zoo kawg coj mus muag tseem ceeb rau tib neeg. Xav txog cov tshuaj yeeb dej caw ntau.

Keeb kwm ntawm lub foundations neeg sawv cev

Tus thawj mention ntawm lub compound rau cov khoom nws tsa sodium hydroxide, tshwm sim txawm nyob rau hauv ancient sij hawm. Txawm phau Vajlugkub muaj ib co lus qhia txog neter tshuaj rho tawm los ntawm Iyiv pas dej. Tej zaum qhov no yog qhov caustic dej qab zib.

Aristotle, Plato thiab lwm yam ancient Greek thiab Roman philosophers thiab zaum kuj raug xa mus nitrum tshuaj uas yog muab rho tawm los ntawm tej yam ntuj tso reservoirs thiab muag nyob rau hauv daim ntawv ntawm cov loj tej daim ntawm txawv xim (dub, grey, dawb). Tom qab tag nrho, txoj kev ntawm kev kho mob twg tseem tsis tau paub dab tsi, yog li lub cais kev twb kev txuas los ntawm thee, polluting nws, nws twb tsis tau.

Nyob rau hauv 385 BC, twb tau muab siv xab npum-txiav txim siab. Cov txheej txheem raws li nyob rau hauv sodium hydroxide siv. Cov mis nws twb tsis tau paub tseeb, tab sis nws tsis ua mob rau extract nws los ntawm lub ashes ntawm cov nroj tsuag ntawm lub genus Salsola, los ntawm cov pas dej thiab siv rau tu tsev neeg cov khoom, khaub ncaws, manufacture ntau yam soaps.

Me ntsis tom qab as kawm ntxiv rau cov khoom tseem ceeb roj, fragrances. Ces cov tshuaj ntxuav tes yog ib tug zoo thiab qab ntxiag daws qhov teebmeem ntawd. Nws pib active kev loj hlob ntawm xab npum txiav txim siab dab thiab yees.

Kom txog thaum lub XVII xyoo pua, caustic dej qab zib, uas nws khoom no siv nyob rau hauv tag nrho, raws li ib tug tshuaj compound tseem unstudied. Nws ua ke nrog rau tej yam li sodium, hydroxide , poov tshuaj carbonate, sodium. Tag nrho cov ntawm lawv twb hu ua caustic alkalis.

Tom qab ntawd tus paub txog Duhamel du Monceau tau los ua pov thawj rau qhov sib txawv ntawm cov tshuaj thiab muab faib lawv mus rau hauv alkali thiab ntsev. Txij li thaum caustic dej qab zib thiab yog nws yeej muaj tseeb thiab qhov rau hnub no lub npe.

txhais npe

Nws yuav tsum tau muab sau tseg hais tias lub npe ntawm no substance yog tsis tau tib yam thiab muaj ob peb lus. Txhua yam yuav raug xaiv 6 hom kev xaiv:

• sodium hydroxide;
• sodium hydroxide;
• caustic dej qab zib;
• sodium alkali;
• caustics;
• caustic alkali.

Caustic dej qab zib , qhov no compound yog hu ua nyob rau hauv ntau thiab kev lag luam. Cov tshuaj synthesis yog ntau yog hais sodium lye los yog caustic dej qab zib. Cov mis tseem zoo li qub. Qhov tseem zoo tib yam lub npe - caustics. Qhov zoo tshaj plaws nyob rau hauv cov nqe lus ntawm kev nomenclature lub npe tshuaj yog sodium hydroxide.

Cov tshuaj mis thiab molecular qauv

Yog hais tias lub yam khoom uas yog xam tau tias yog los ntawm lub standpoint ntawm Science News for KIDS, nws yuav muaj xws li ob ions: sodium ntawv (Na ⁺⁾ thiab hydroxide anion (OH ^-). Kev Tiv Tauj txhua lwm yam vim electrostatic attraction raznozaryazhennyh hais, cov ions tsim sodium hydroxide. Empirical mis ntawm daim ntawv yog NaOH.

Gidroksogrupp tsim covalent ncov qaumteb qabteb daim ntawv cog lus ntawm cov pa thiab hydrogen, nyob rau nws yog muaj nyob rau nrog sodium ionic daim ntawv cog lus. Lub alkali tov yog kiag li dissociated rau hauv ions, ua ib tug muaj zog ntsha.

Kuaj txoj kev ua

Muaj thiab cov kev ua sim rau qhov kev npaj ntawm sodium hydroxide zoo echoes. Feem ntau nyob rau hauv me me qhov ntau nws yog tau los ntawm tshuaj thiab electrochemical txoj kev nyob rau hauv me me units tshaj nyob rau hauv industrial cov chaw. Ib tug tuj ntawm lub substance ua los ntawm cov tib txoj kev mus rau loj loj colonies ntawm lub hlwb.

Muaj ntau ntau yooj yim txoj kev rau lub synthesis ntawm caustic nyob rau hauv cov kev kuaj.

1. Ferritic txoj kev. Nws muaj ob lub ntsiab theem: thawj sintering nyob rau hauv kub sodium carbonate thiab hlau oxide (III). Qhov no ua sodium ferrite (NaFeO _2). Thaum lub thib ob theem, nws yog raug dej thiab decomposes tsim sodium hydroxide thiab dej tov nrog hlau (Fe ₂ O ₃ * H ₂ O). Cov uas ua caustic dej qab zib tov yog evaporated rau ntawm muaju los yog dawb ya ri tau. Nws kev coj dawb huv yog hais txog 92%.
2. Txiv qaub txoj kev. Cov tshuaj tiv thaiv yog cov kev sis raug zoo ntawm sodium carbonate thiab calcium hydroxide (slaked txiv qaub) tsim calcium carbonate thiab caustic. Cov tshuaj tiv thaiv yog ua nyob rau ntawm lub ib tug kub ^ntawm 80 C. Vim lub resulting ntsev precipitates, nws yog sib cais yooj yim. Qhov seem tov twb evaporated mus muab cov sodium alkali.
3. Lub diaphragm thiab ib txoj kev ua ib tug membrane. Raws li cov kev ua hauj lwm ntawm lub electrolyzer unit. Nws tau txais kev pab tshuaj ntawm ntau ntsev (NaCl), uas yog electrolyzed tsim free ntawm gaseous tshuaj thiab caustic dej qab zib ntau lawm ntawm yam khoom. Qhov txawv nyob rau hauv cov kev yog hais tias thaum tus txheej txheem diaphragm ntsiab yam ntxwv ib feem ntawm tus dais no yog ib tug diaphragm ntawm asbestos (cathode). Thaum lub diaphragm txoj kev cathode thiab anode qhov chaw no tau muab faib los ntawm ib tug tshwj xeeb daim nyias nyias.

Yog li npaj nyob rau hauv txoj kev kuaj thiab sodium hydroxide, xaiv lub feem ntau yooj yim nyob rau hauv kev xaiv cov ntaub ntawv uas cov ntsiab lus uas. Nws yog, raws li ib tug txoj cai, tsawg zog-intensive.

Synthesis nyob rau hauv kev lag luam

Yuav ua li cas yog xws li ib tug yeeb tshuaj nyob rau hauv kev ua lag luam, xws li sodium hydroxide? Kua thiab khoom caustic dej qab zib yog ua feem ntau los ntawm electrochemical txoj kev. Nws yog raws li nyob rau hauv electrolysis ntawm kev daws ntawm ib tug tej yam ntuj tso mineral halite, feem ntau ntawm uas yog tsim nrog sodium tshuaj dawb.

Lub ntsiab feature ntawm no synthesis yog hais tias lub by-khoom nrog sodium hydroxide yog gaseous tshuaj thiab hydrogen. Cov txheej txheem yog nqa tawm nyob rau hauv ib yam ntawm cov peb kev xaiv:

• diaphragm rau electrolysis khoom cathode;
• ntawm cov kua mercury cathode;
• membrane nrog ib tug khoom cathode.

Feem coob ntawm cov caustic dej qab zib nyob rau hauv lub ntiaj teb no yog ua los ntawm cov qauv no yog tseem nrog cov daim nyias nyias. Cov uas ua alkali txawv sufficiently theem siab ntawm kev coj dawb huv.

daim ntawv sau npe

Muaj ntau ntau industries nyob rau hauv uas lub sij sodium hydroxide. Daim ntawv thov raws li nyob rau hauv nws cov tshuaj thiab lub zog, ua qhov no compound indispensable nyob rau hauv ntau syntheses thiab cov txheej txheem.

Muaj ntau ntau yam loj tej qhov chaw uas sodium hydroxide - ib tug yuav tsum caij.

1. Tshuaj ntau lawm (synthesis ntawm esters, soaps, Sibhawm, zus tau tej cov fibers, txhuas etching, los ua kom zoo zoo cov khoom, raws li ib lub hauv paus nyob rau hauv ntau cov txheej txheem, ib tug yooj yim tshuaj rau neutralize lub acids thiab lawv coj oxides; nyob rau hauv analytical Science News for KIDS yog siv rau cov titration; kuj yog siv tau rau kom tau ntshiab co, ntau ntsev ntawm lwm bases thiab organic tebchaw).
2. Nyob rau hauv daim ntawv siv, rau cov kev kho mob ntawm cov ntoo sis plawv hniav (ntoo tshuaj pov tseg ntawm lignin).
3. Cov tib neeg economic kev ua si no kuj yog indispensable caustic dej qab zib. Cov kev siv ntawm ntau detergents thiab tu khoom raws li nws yog ib qho tseem ceeb heev. Xab npum, tsuaj zawv plaub hau tau txais - tag nrho cov no tsis yog tsis muaj caustic.
4. Yog yuav tsum tau rau lub synthesis ntawm biofuels.
5. Hos nyob rau hauv ib lub teb chaws teev rau cov tshem tej paug thiab neutralization ntawm tej yam tshuaj lom, los ntawm lub cev.
6. Qhuav ntawm cov tshuaj thiab tshuaj yeeb.
7. Khoom noj khoom haus kev lag luam - confectionery, qhob noom xim kasfes, cocoa, mis nyuj khov, khoom qab zib, coloring, tau cov txiv ntseej, pastry bakery cov khoom.
8. Nyob rau hauv cosmetology kev tshem tawm cov txawv teb chaws cov chaw (moles, papilloma cos).
9. Siv rau haus dej haus cawv thiab haus luam yeeb mills.
10. Nyob rau hauv lub textile kev lag luam.
11. Khob: xim, zoo, thiab lwm yam kho qhov muag.

Nws yog tshwm hais tias sodium hydroxide - ib tug tseem ceeb heev thiab pab tau nyob rau hauv tib neeg kev ua si substance. Nws tsis yog nyob rau hauv vain, nws yog tsim nyob rau hauv tons txhua xyoo nyob rau hauv lub ntiaj teb no - 57 lab los yog ntau tshaj.

lub zog

Dawb powdery yeeb tshuaj, tej zaum tsis muaj kob. Nws tej zaum yuav nyob rau hauv daim ntawv ntawm cov zoo crystalline hmoov los yog nyob rau hauv daim ntawv ntawm cov plaub ya ri. Feem ntau nyob rau hauv daim ntawv ntawm cov loj muaju. Lub melting point yog heev tsawg - 65,1 ^C. Heev sai sai absorbs noo noo thiab yuav hydrated daim ntawv 3,5N NaOH · ₂ O. Nyob rau hauv cov ntaub ntawv no, lub melting kub yog tseem tsawg, tsuas 15.5 ^C. Xyaum unlimited soluble nyob rau hauv alcohols, dej . Yuav kom qhov kov raws li ib tug khoom thiab kua xub npus.

Heev txaus ntshai nyob rau hauv feeb meej thiab diluted daim ntawv. Peev xwm ntawm ua tag nrho ntawm lub qhov muag mus txog rau lub optic paj. Qhov muag hu yuav ua nyob rau hauv txoj kev dig muag. Yog li ntawd, ua hauj lwm nrog rau qhov no compound tsis tshua muaj neeg txaus ntshai thiab yuav tsum tau kev tiv thaiv pab kiag li lawm.

tshuaj zog

Caustic dej qab zib zog teev raws nraim tib yam li tag nrho cov alkali: yog reacted nrog ib tug acid, acid oxides, amphoteric oxides thiab hydroxides, ntsev. Ntawm Nonmetallic reacts nrog cov leej faj, phosphorus thiab halogens. Tsis tas li ntawd muaj peev xwm ntawm reacting nrog hlau.

Nyob rau hauv cov organic Science News for KIDS, sodium hydroxide reacts nrog amides, esters, halogenated alkanes.

cia tej yam kev mob

Cia ntawm caustic dej qab zib yog nqa tawm nyob rau hauv tej yam tej yam kev mob. Qhov no yog vim hais tias nws yog tsis tshua muaj reactive, tshwj xeeb tshaj yog thaum noo. Cov yooj yim tej yam kev mob yog cov nram qab no.

1. Khaws tseg los ntawm cov cua kub cov khoom siv.
2. Hermetically kaw thiab kaw ntim yog tsis muaj peev xwm sawv ntawm kis ya raws.
3. Qhuav crystalline caustics muab cia rau hauv sacks ntawm tshwj xeeb pes tsawg leeg (tuab polyethylene), ib tug kua - nyob rau hauv qhov tsaus ntuj nti iav fwj cov av iav stoppers. Yog hais tias lub xov tooj yog loj thiab yuav tsum tau cov kev thauj mus los, cov sodium hydroxide tshuaj twb muab tso nyob rau hauv tshwj xeeb ntim thiab steel poom.

Cov tshuaj yeeb dej caw yuav raug thauj mus los ntawm tej yam paub txoj kev nyob rau hauv kev ua raws cai nrog kev ruaj ntseg cov kev cai, xa kev thauj mus los los ntawm huab cua.

Kua sodium lye

Dhau li siv lead ua, muaj ib tug aqueous tov ntawm sodium hydroxide. Nws yog tib yam mis raws li rau qhov khoom. Sib daws teeb meem ntau pab tau thiab yooj yim rau siv. Yog li ntawd, nyob rau hauv xws li ib tug daim ntawv caustics siv ntau feem ntau.

Ib tug tov ntawm sodium hydroxide uas nws mis - NaOH, yog siv nyob rau hauv tag nrho cov ntawm cov chaw no. Nws yog tsis yooj yim xwb thaum lub sij hawm thauj mus los, raws li thauj yog zoo dua mus rau qhuav caustic. Rau tag nrho lwm yam khoom tsis paib muaju, thiab nyob rau hauv ib txhia thiab surpasses lawv.