Hydrofluoric acid

Hydrofluoric acid yog feem ntau nyob rau hauv daim ntawv ntawm ib tug 40% daws, tiam sis tej zaum kuj muaj 50% los yog 72% daws teeb meem. Tsis tau nws yog hu ua ib tug hydrofluoric acid los yog aqueous hydrogen fluoride. Nws lub npe twb tsim los ntawm fluorspar, los ntawm uas, nyob rau hauv lem, yog hydrogen fluoride.

Hydrofluoric acid - nws mis HF. Dig muag, nws yog ib tug tsis muaj kob kua, muaj ib tug molecular ceeb thawj los ntawm 20,0063 g / mol thiab ib tug ntom - 1.15 g / cm³. Nws yog yus muaj los ntawm kub: Melting - 83,6 ° C, tus kub - 19,5 ° C. Nws yog uas tsis yog-flammable thiab mas lom.

Yuav ua li cas nta muaj hydrofluoric acid? Cov mis ntawm no cov ntaub ntawv uas qhia tias muaj xws li fluorine thiab hydrogen nyob rau hauv nws cov qauv. Nws belongs rau lub thib ob chav kawm ntawv ntawm kev txaus ntshai, raws li tsim los ntawm lub dissociation ntawm fluorine yog tshuaj lom thiab tej rau peb ib puag ncig.

Thaum xaus ntawm lub acid nyob rau hauv cov dej nyob hauv ib tug npaum li ntawm tshav kub yog 59,1 kJ / mol. Nws reacts nrog ntau co, li no txoj kev fluorides. Nthuav yog qhov tseeb hais tias txawm ib tug me me ib feem ntawm cov no acid yog muaj peev xwm sawv ntawm tej lub freezing point ntawm dej txheem. Thaum uas tsis muaj kub hydrogen fluoride hauv qab no tebchaw nrog dej H2O · HF, H2O thiab H2O · 2HF · 4HF.

Txawm tias muaj tseeb hais tias cov hydrofluoric acid belongs rau nruab nrab lub dag lub zog acids, nws corrodes thiab silicate iav ntim. Tsis tas li ntawd, nws yog ib lub xwb ib tug ntawm nws chav kawm ntawv yam khoom uas uas reacts nrog silicon oxide SiO (2). Qhov no oxide, nyob rau hauv lem, yog lub ntsiab khoom siv rau lub khob lawm. Hydrofluoric acid muaj tsis ntxim rau cov ciab, ces nws yog dav siv rau nws cia. Thaum lub tam sim no lub sij hawm nws yog thauj thiab khaws tseg xwb nyob rau hauv cov hnab yas pob, los yog ua los ntawm roj hmab thiab cov hlau lead ntim. High concentration (60%) acid tej zaum yuav nqa nyob rau hauv muaj zog ntim ua los ntawm steel.

Co, uas yog tsis soluble nyob rau hauv nws, nws ua, platinum thiab kub. Kev hydrofluoric acid muaj ob peb impurities, cov uas feem ntau yog xws li Fe, Rb, Raws li, thiab N2SiF6, SO2. Zoo tu acid yog tau los ntawm hloov nws mus rau potassium difluoride. Ntxiv mus, nws yog decomposed thiab yaj los ntawm cua sov rau cov hydrogen fluoride hauv dej.

Thaum ua hauj lwm nyob rau hauv lub chaw soj nstuam siv cov tais diav thiab ntim ntawm polyethylene thiab PTFE, thiab loj tagnrho cov hydrofluoric acid muab cia rau hauv steel, kaw ntom nti, hermetically kaw tso tsheb hlau luam, thiab tso tsheb hlau luam los yog thooj voos kheej kheej ammonia yam, uas yuav tsum tau muaj ib tug tiv thaiv coloring muaj.

Hydrofluoric acid yog txaus ntshai rau tib neeg noj qab haus huv. Nws muaj ib tug tsis muaj zog narcotic ntxim rau cov psyche. Yog hais tias rau ib co yog vim li cas nws tau txais mus rau hauv cov ntshav, nyob rau hauv cov ntaub ntawv no kom tsis txhob muaj mob loj heev lom nrog ib tug kev hloov nyob rau hauv lub zog ntawm lub digestive system thiab pulmonary edema. Txawm hydrofluoric acid peev xwm cuam tshuam lub plawv ua si thiab kev intoxication ntawm tus kab mob.

Nyob rau hauv kev sib cuag nrog cov tawv nqaij los yog qhov muag, nws ua rau mob kub yus txawm nyob rau hauv uas tsis muaj ntau. Tshwj xeeb tshaj yog tsis kaj siab txim ntawm acid allergic los ntawm tes, thiaj ua rau nws tsuas xav kom looj hnab looj tes thiab ib tug zoo stretch.

Yog hais tias, li ntawd xwb, daim tawv nqaij tau txais acid, ces sai sai yaug nws nrog khiav dej thiab kho nrog 2.5% calcium gluconate raws li ib tug gel. Tab sis hais tias tsis tau nres, koj yuav tsum tau nrog koj tus kws kho mob tam sim ntawd. Nws yuav xaiv ib tug tso dej txhaj tshuaj ntawm poov hlau tshuaj dawb.

Qhov twg yog siv no txaus ntshai acid? Tam sim no, nws yog nquag siv nyob rau hauv cov pob zeb ua hauj lwm ntawm silicate yaj co xws li niobium, tantalum thiab zirconium. Nws ua raws li ib lub hauv paus rau lub hydrogenation thiab dehydrogenation, raws li zoo raws li nyob rau hauv qhov siv thiab ua fluoropolymers, freons thiab fluorosulfonic acid. Nws pom nws daim ntawv thov nyob rau hauv cov roj kev lag luam. Nws twb kho nrog roj qhov dej lug txhim khu cov roj ntau lawm.