Silicic acid thiab nws daim ntawv thov

Silicic acid raws yog ib tug compound ntawm silicon oxide thiab dej. Wherein tus piv ntawm nws cov Cheebtsam yuav ua tau heev ntau yam. Yog li ntawd, nyob rau hauv kev nws muaj pes tsawg leeg yuav sawv cev los ntawm lub mis. Nyob rau hauv cov ntaub ntawv no silicic acid nrog lub xub ntiag ntawm txawv cov nqi ntawm cov pob zeb ntais oxide thiab dej, uas yog, nrog txawv tseem ceeb ntawm cov tsis n thiab m, yuav yooj yim txav los ntawm ib lub xeev mus rau lwm lub. Yog li, n thiab m nyob rau hauv cov ntaub ntawv no muaj peev xwm yuav ntshai li ntau yam.

Nyob rau hauv kev tshawb xav, silicic acid yuav tsum npaj kom txhij los ntawm reacting ib silicate ntawm ib tug alkali hlau (e.g. sodium) thiab ib tug "muaj zog" acids (e.g., hydrochloric acid). Nyob rau hauv no txoj kev, nyob rau hauv lub dawb lub xeev tau muab cais tawm (npaj), ib txhia ntawm cov acids: metasilicic, orthosilicic thiab lwm tus neeg. Piv txwv li, ib tug tshuaj cov tshuaj tiv thaiv ua metasilicic acid:

+ 2HCl = + 2NaCl

Txawm li cas los, kom tau ib tug dawb huv silicic acid yog yuav luag tsis yooj yim sua. Nyob rau hauv aqueous lub ntsiab (thiab lawv tau supersaturated) silicic acid nyob rau hauv lub polymerization txheej txheem tsis tu tsis tseg hauv paus tsim ntawm colloidal kev daws teeb meem nrog ib tug es luv luv lub sij hawm ntawm cov hav zoov. Ntxiv cov ntsiab ntawm cov gel tsim los ntawm coagulation. Nyob rau ntawd cov lus dag siv ntawm silicic acid, vim nws yog drained gel muab qhov thiaj li hu ua silica, uas yog siv raws li ib tug desiccant thiab ntxeem tau dej. Nyob rau hauv tas li ntawd, los ntawm kev siv tshwj xeeb stabilizers, npaj los ntawm colloidal kev daws teeb meem ruaj khov colloids (los yog sols) uas kuj nrhiav tau daim ntawv thov nyob rau hauv qhov.

Silicic acid yog tsis zoo soluble, thermally tsis ruaj tsis khov thiab tsis muaj zog. Thaum rhuab, lub decomposition ntawm lub silicic acid uas yog qhia los ntawm cov nram qab no tshuaj cov tshuaj tiv thaiv:

=

Nws kuj yog ib tug weaker acid tshaj tib thee. Los ntawm virtue ntawm no silicic acid nyob rau hauv aqueous lub ntsiab yog moog carbonic acid los ntawm nws cov ntau ntsev. Raws li ib qho piv txwv, nws yuav pom nyob rau hauv cov tshuaj tiv thaiv:

= +

Silicic acid ntsev hu ua silicates. Lawv muaj ib tug dav tis rau xwm. Piv txwv li, nyob rau hauv lub ntiaj teb ua kiav txhab mas muaj silicas thiab silicates. Cov no muaj xws Feldspar, ntau yam txais av ya, mica, talc, thiab ntau lwm tus neeg. Silicates yog muaj nyob rau hauv nyob tus yeees ntawm cov pob zeb - granite, basalt, thiab lwm tus neeg. Silicate muaju muaj xws li zoo-paub gems, uas, vim hais tias ntawm lawv cov rarity thiab kev zoo nkauj yog suav tias yog precious li emeralds, topaz thiab aquamarine.

Feem ntau ntawm cov silicates insoluble nyob rau hauv cov dej. Cov xwb yog sodium silicates thiab poov tshuaj. Lawv muaj peev xwm muab tau los ntawm alloying nrog cov coj hydroxide los yog carbonate. Piv txwv li,

+ + =

Aqueous lub ntsiab ntawm lub ntsev tau nyob rau hauv no txoj kev no hu ua "waterglass". Nws pom dav siv raws li ib tug phau ntawv nyob rau hauv zus tau tej cov acid-resistant ua vaj tse, thiab nyob rau hauv tas li ntawd, siv nyob rau hauv qhov siv thiab ua tag nrho cov paub putty thiab daim ntawv lo. Raws li ib tug nplaim taws retardant thiab waterproof Impregnating lawv kuj ua khoom ua los ntawm ntaub, ntoo thiab daim ntawv.

Silicates, raws li ib feem ntawm uas yog txhuas, tau txais tis npe aluminosilicate. Cov no muaj xws mica thiab Feldspar, txawm hais tias lawv cov qauv yog ntau npaum li cas complicated. Yog li, Feldspar, tsuas yog pob zeb ntais oxide thiab txhuas oxide tseem muaj oxides ntawm sodium, potassium, thiab sodium. Nyob rau hauv nyob tus yeees ntawm mica, nyob rau hauv tas li ntawd mus txhuas thiab pob zeb ntais, nws muaj ib tug hydrogen, sodium los yog poov tshuaj, tab sis tej zaum yuav, txawm hais tias tsis tshua muaj heev, kuj calcium, magnesium los yog hlau.

Nyob rau hauv dav dav, lub siv ntawm silicates nyob rau hauv lub tam sim no tej yam kev mob yog sab heev thiab ntau haiv neeg. Roob silicate pob zeb yog siv raws li lub tsev ntaub ntawv. Silicates siv raws li ib tug raw khoom nyob rau hauv cement manufacturing, ntau yam fillers, ceramics, iav, thiab li ntawd. Mica thiab asbestos yog siv rau lub zus tau tej cov ntau yam thermal thiab hluav taws xob insulating cov ntaub ntawv.