zvigadzirwa

Girazi remvura

26.05.2022 /

Liquid glass is a concentrated solution ye sodium metasilicate Na2SiO3 (potassium munyu inoshandiswawo). Inogadzirwa nekunyungudutsa silica (sejecha) mune sodium hydroxide solution: 

Girazi remvura kutaura zvazviri, musanganiswa wemunyu weasidhi yakasiyana-siyana ine madhigirii akasiyana epolymerization. Inoshandiswa sekuisa pamuviri (somuenzaniso, kudzivirira masvingo kubva kune unyoro, sekudzivirira moto), chikamu cheputty uye sealants, pakugadzirwa kwezvinhu zvesilicone, pamwe chete nekuwedzera kwezvokudya kudzivirira caking (E 550). Girazi remvura rinowanikwa pakutengesa rinogona kushandiswa pakuedza kwakati wandei (nekuti imvura yakakora ine muto, inoshandiswa yakadirwa 1:1 nemvura).

Mukuedza kwekutanga, isu tichagadzirisa musanganiswa wesiliciic acids. Pabvunzo, isu tichashandisa zvinotevera mhinduro: girazi remvura uye ammonium chloride NH.4Cl uye pepa rechiratidzo chekutarisa maitiro (mufananidzo 1).

Chemistry - chikamu chegirazi remvura 1 - MT

Girazi remvura semunyu weasidhi isina kusimba uye chigadziko chakasimba mumushonga wemvura unonyanya kuve nehydrolyzed uye ine alkaline (mufananidzo 2). Dururira ammonium chloride solution (mufananidzo 3) mubeaker ine mvura yegirazi mhinduro uye simbisa zviri mukati (mufananidzo 4). Mushure mechinguva, gelatinous mass inoumbwa (mufananidzo 5), inova musanganiswa we sililic acid:

(parutivi rweSiO2нГн2ABOUT ? silicic acids ine madhigirii akasiyana e hydration anoumbwa).

Iyo beaker reaction mechanism inomiririrwa nepfupiso iri pamusoro apa ndeiyi inotevera:

a) sodium metasilicate mumhinduro inoparadzanisa uye inopinda hydrolysis:

b) ammonium ions inopindirana neion hydroxide:

Sezvo hydroxyl ions inopedzwa mukuita b), iyo yakaenzana yekuita a) inoshanduka kuenda kurudyi uye, semhedzisiro, silicic acid inonaya.

Mukuedza kwechipiri, tinokura "makemikari zvirimwa". Mhinduro dzinotevera dzichadikanwa pakuedza: girazi remvura uye munyu wesimbi? iron (III), iron (II), mhangura (II), calcium, tini (II), chromium (III), manganese (II).

Chemistry - chikamu chegirazi remvura 2 - MT

Ngatitangei kuyedza nekuunza akati wandei makristasi esimbi chloride (III) munyu FeCl muchubhu yekuyedza.3 uye mhinduro yegirazi remvura (mufananidzo 6). Mushure mechinguva, brown?zvinomera? (mufananidzo 7, 8, 9), kubva musimbi isinganyunguriki (III) metasilicate:

Zvakare, munyu weimwe simbi inobvumidza iwe kuti uwane mibairo inoshanda:

  • mhangura(II)? mufananidzo 10
  • chromium(III)? Mufananidzo 11
  • simbi(II)? Mufananidzo 12
  • calcium? Mufananidzo 13
  • manganese(II)? Mufananidzo 14
  • tin(II)? Mufananidzo 15

Iyo nzira yekuenderera mberi kwemaitiro inobva pane chiitiko che osmosis, kureva, kupinda kwezvikamu zviduku kuburikidza ne pores ye semipermeable membranes. Deposits of insoluble metal silicates inoumba sechidimbu chakatetepa pamusoro pemunyu unounzwa muchubhu yebvunzo. Mamorekuru emvura anopinda mumapores e membrane inobuda, zvichiita kuti munyu wesimbi uri pasi unyunguduke. Mhinduro inoguma inosundira firimu kusvikira yaputika. Mushure mekudurura munyu wesimbi, iyo silicate inonaya inonaya zvakare? kutenderera kunozvidzokorora uye makemikari chirimwa? inowedzera.

Nokuisa musanganiswa wemakristasi emunyu wesimbi dzakasiyana-siyana mumudziyo mumwe uye wodiridza nemuganho wegirazi rinoyerera, tingarima here “bindu remakemikari” rose? (Mufananidzo 16, 17, 18).

Mifananidzo

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