Dilute thiab concentrated sulfuric acid yog cov tshuaj tseem ceeb uas lub ntiaj teb tsim tau ntau dua li lwm yam khoom. Kev khwv nyiaj txiag ntawm ib lub teb chaws tuaj yeem ntsuas los ntawm cov nyiaj sulfuric acid uas nws tsim.
txheej txheem kev sib cais
Sulfuric acid yog siv nyob rau hauv daim ntawv ntawm aqueous daws ntawm ntau yam concentrations. Nws dhau los ua qhov kev sib cais ntawm ob kauj ruam, tsim H+ ions hauv kev daws.
H2SO4 =H+ + HSO4 -;
HSO4- =H + + SO4 -2.
Sulfuric acid yog muaj zog, thiab thawj theem ntawm nws dissociation yog khaus heev uas yuav luag tag nrho cov thawj molecules decompose rau hauv H+-ions thiab HSO 4 -1 -ions (hydrosulfate) hauv cov tshuaj. Cov tom kawg ib nrab lwj ntxiv, tso lwm H+-ion thiab tawm hauv sulfate ion (SO4-2) hauv kev daws teeb meem. Txawm li cas los xij, hydrogen sulfate, ua cov kua qaub tsis muaj zog, tseem muaj yeej.in solution over H+ and SO4-2. Nws tag nrho dissociation tshwm sim tsuas yog thaum qhov ntom ntawm sulfuric acid tov mus txog qhov ntom ntawm cov dej, uas yog, muaj zog dilution.
Khoom ntawm sulfuric acid
Nws yog qhov tshwj xeeb uas nws tuaj yeem ua raws li cov kua qaub ib txwm muaj lossis ua cov oxidizing muaj zog, nyob ntawm nws qhov kub thiab txias. Ib tug txias dilute daws ntawm sulfuric acid reacts nrog active hlau los tsim ib tug ntsev (sulfate) thiab tso hydrogen gas. Piv txwv li, cov tshuaj tiv thaiv ntawm txias dilute H2SO4 (xav tias nws ua tiav ob-theem dissociation) thiab hlau zinc zoo li no:
Zn + H2SO4 = ZnSO 4+ H2.
Kub concentrated sulfuric acid, nrog rau qhov ntom ntawm li 1.8 g / cm3 , tuaj yeem ua tus neeg sawv cev oxidizing, ua rau cov khoom siv uas feem ntau inert rau acids, xws li zoo li hlau tooj liab. Thaum lub sij hawm cov tshuaj tiv thaiv, tooj liab yog oxidized, thiab qhov loj ntawm cov kua qaub txo, ib tug tov ntawm tooj liab (II) sulfate nyob rau hauv dej thiab gaseous sulfur dioxide (SO 2) es tsis txhob hydrogen yog tsim, uas yuav xav tau thaum cov kua qaub reacts nrog hlau.
Cu + 2H2SO4 =CuSO4 + SO 2 + 2H2 O.
Yuav ua li cas yog qhov concentration ntawm cov kev daws teeb meem feem ntau qhia
Qhov tseeb, qhov concentration ntawm ib qho kev daws teeb meem tuaj yeem nthuav tawm txawvtxoj kev, tab sis feem ntau siv hnyav concentration. Nws qhia tus naj npawb ntawm grams ntawm cov kuab tshuaj nyob rau hauv ib tug muab mass los yog ntim ntawm ib tug tov los yog hnyav (feem ntau 1000 g, 1000 cm3, 100 cm 3 thiab 1 dm 3). Hloov chaw ntawm cov khoom hauv grams, koj tuaj yeem noj nws cov nyiaj tau hais hauv moles - tom qab ntawd koj tau txais cov molar concentration ib 1000 g lossis 1 dm 3 daws.
Yog hais tias cov molar concentration yog txhais nyob rau hauv kev sib raug zoo tsis mus rau tus nqi ntawm cov tshuaj, tab sis tsuas yog rau cov hnyav, ces nws yog hu ua molality ntawm cov tshuaj. Nws yog tus yam ntxwv los ntawm kev ywj pheej los ntawm qhov kub thiab txias.
Feem ntau, qhov hnyav hnyav yog qhia hauv grams ib 100 g ntawm hnyav. Muab cov duab no los ntawm 100%, koj tau txais nws hauv qhov hnyav feem pua (feem pua ntawm cov concentration). Nws yog txoj kev no uas feem ntau siv rau hauv daim ntawv thov rau sulfuric acid daws.
Txhua tus nqi ntawm qhov concentration ntawm cov tshuaj tau txiav txim siab ntawm qhov ntsuas kub sib haum rau nws qhov tshwj xeeb ntom ntom (piv txwv li, qhov ntom ntawm cov tshuaj sulfuric acid). Yog li ntawd, qee zaum qhov kev daws teeb meem yog qhov tseeb los ntawm nws. Piv txwv li, kev daws teeb meem ntawm H2SO4, tus cwj pwm los ntawm qhov feem pua ntawm 95.72%, muaj qhov ceev ntawm 1.835 g / cm3 ntawm t=20 °С. Yuav ua li cas txiav txim siab qhov concentration ntawm xws li kev daws, yog tias tsuas yog qhov ntom ntawm sulfuric acid muab? Ib lub rooj muab cov ntawv xov xwm zoo li no yog ib feem tseem ceeb ntawm txhua phau ntawv qhia txog kev siv tshuaj lom neeg lossis tshuaj lom neeg.
Piv txwv ntawm kev hloov pauv siab
Cia peb sim txav los ntawm ib txoj hauv kev qhia kom pom tseebdaws rau lwm tus. Piv txwv tias peb muaj ib qho kev daws teeb meem ntawm H2SO4
60%. Ua ntej, peb txiav txim siab qhov sib thooj ntawm sulfuric acid. Ib lub rooj uas muaj feem pua ntawm cov concentrations (thawj kem) thiab lawv qhov sib thooj ntawm cov tshuaj aqueous ntawm H2SO4 (them plaub) yog qhia hauv qab no.
Los ntawm nws peb txiav txim siab tus nqi uas xav tau, uas yog sib npaug rau 1,4987 g / cm3. Cia peb tam sim no suav cov molarity ntawm cov tshuaj no. Txhawm rau ua qhov no, nws yog ib qho tsim nyog los txiav txim siab qhov loj ntawm H2SO4 hauv 1 liter ntawm tshuaj thiab tus naj npawb ntawm moles ntawm acid.
ntim tau los ntawm 100 g ntawm cov tshuaj hauv Tshuag:
100 / 1, 4987=66.7 ml.
Vim 66.7 milliliters ntawm 60% tov muaj 60 g ntawm acid, 1 liter ntawm nws yuav muaj:
(60 / 66, 7) x 1000=899.55
Cov molar hnyav ntawm sulfuric acid yog 98. Yog li, tus lej ntawm moles muaj nyob rau hauv 899.55 g ntawm nws cov grams yuav yog:
899, 55 / 98=9, 18 mol.
Qhov kev vam khom ntawm qhov ntom ntawm sulfuric acid ntawm qhov concentration yog qhia hauv daim duab. hauv qab no.
Siv sulfuric acid
Nws yog siv rau hauv ntau yam kev lag luam. Hauv kev tsim cov hlau thiab hlau, nws yog siv los ntxuav qhov saum npoo ntawm cov hlau ua ntej nws yog coated nrog lwm cov khoom, nws yog koom nrog hauv kev tsim cov khoom siv hluavtaws, nrog rau lwm hom acids, xws li hydrochloric thiab nitric. Nws kujsiv nyob rau hauv kev tsim tshuaj, chiv thiab explosives, thiab kuj yog ib qho tseem ceeb reagent nyob rau hauv lub tshem tawm impurities los ntawm cov roj nyob rau hauv cov roj refining kev lag luam.
Cov tshuaj no muaj txiaj ntsig zoo hauv tsev, thiab tau yooj yim muaj los ua cov tshuaj sulfuric acid siv hauv cov roj teeb txhuas (xws li cov pom hauv tsheb). Cov kua qaub no feem ntau muaj qhov concentration ntawm li 30% mus rau 35% H2SO 4 los ntawm qhov hnyav, nrog rau qhov seem yog dej.
Rau ntau daim ntawv thov hauv tsev, 30% H2SO4 yuav ntau tshaj li qhov koj xav tau. Txawm li cas los xij, kev lag luam kuj yuav tsum muaj ntau dua cov ntsiab lus ntawm sulfuric acid. Feem ntau, thaum lub sij hawm tsim cov txheej txheem, nws thawj zaug hloov mus rau heev diluted thiab kis nrog cov organic impurities. Cov concentrated acid tau txais nyob rau hauv ob theem: thawj zaug nws yog coj mus rau 70%, thiab tom qab ntawd - nyob rau hauv lub thib ob theem - nws yog nce mus rau 96-98%, uas yog txwv rau kev lag luam kev lag luam.
Qhov ntom ntawm sulfuric acid thiab nws qib
Txawm hais tias yuav luag 99% sulfuric acid tuaj yeem tau luv luv los ntawm boiling, tom qab poob ntawm SO3 ntawm boiling point txo qhov concentration mus rau 98.3%. Feem ntau, 98% ntau yam ruaj khov hauv kev cia.
Cov qib lag luam ntawm cov kua qaub sib txawv ntawm nws qhov feem pua ntawm cov concentration, thiab rau lawv cov txiaj ntsig tau xaiv ntawm qhov kub ntawm crystallization tsawg. Qhov no yog ua los txo cov nag lossis daus ntawm sulfuric acid crystals.sediment thaum thauj thiab khaws cia. Lub ntsiab ntau yam yog:
- Tower (nitrous) - 75%. Qhov ceev ntawm sulfuric acid ntawm qib no yog 1670 kg / m 3. Tau txais nws lub npe. Nitrous txoj kev, nyob rau hauv uas cov roasting roj tau txais thaum lub sij hawm roasting ntawm thawj raw cov ntaub ntawv, muaj sulfur dioxide SO 2, nyob rau hauv lined yees (li no lub npe ntawm ntau yam) yog kho nrog nitrous (qhov no. kuj yog H2 SO4, tab sis nrog nitrogen oxides yaj hauv nws). Raws li qhov tshwm sim, cov kua qaub thiab nitrogen oxides raug tso tawm, uas tsis siv rau hauv cov txheej txheem, tab sis raug xa rov qab mus rau lub voj voog ntau lawm.
- Hu rau - 92, 5-98, 0%. Qhov ceev ntawm 98% sulfuric acid ntawm qib no yog 1836.5 kg/m 3. Nws kuj tau txais los ntawm roasting gas uas muaj SO2, thiab cov txheej txheem suav nrog oxidation ntawm dioxide rau anhydride SO3 thaum nws los rau hauv kev sib cuag (li no lub npe ntawm ntau yam) nrog ob peb txheej ntawm cov khoom vanadium catalyst.
- Oleum - 104.5%. Nws qhov ceev yog 1896.8 kg/m3. Qhov no yog ib qho kev daws teeb meem ntawm SO3 hauv H2SO4, uas thawj feem muaj 20 %, thiab acids - raws nraim 104.5%.
- % oleum siab - 114.6%. Nws qhov ceev yog 2002 kg/m3.
- Battery - 92-94%.
Lub tsheb roj teeb ua haujlwm li cas
Kev ua haujlwm ntawm qhov no yog ib qho ntawm cov khoom siv hluav taws xob loj tshaj plaws yog ua tiav raws li cov txheej txheem electrochemical tshwm sim nyob rau hauv lub xub ntiag ntawm aqueous tov ntawm sulfuric acid.
Lub tsheb roj teeb muaj dilute sulfuric acid electrolyte thiabzoo thiab tsis zoo electrodes nyob rau hauv daim ntawv ntawm ob peb daim hlau. Cov phaj zoo yog ua los ntawm cov khoom siv xim liab-xim av - lead dioxide (PbO 2), thiab cov phaj tsis zoo yog ua los ntawm greyish "spongy" lead (Pb).
Vim tias cov electrodes yog ua los ntawm cov hlau lead lossis cov khoom siv lead ua, cov roj teeb hom no feem ntau hu ua cov roj lead-acid. Nws qhov kev ua tau zoo, piv txwv li, qhov loj ntawm qhov tso zis hluav taws xob, yog ncaj qha txiav txim siab los ntawm qhov ceev ntawm sulfuric acid tam sim no (kg / m3 lossis g / cm3) ntim rau hauv lub roj teeb raws li electrolyte.
Yuav ua li cas rau electrolyte thaum lub roj teeb tawm
Lub roj teeb lead-acid electrolyte yog ib qho kev daws teeb meem ntawm roj teeb sulfuric acid nyob rau hauv cov tshuaj ntshiab distilled dej ntawm ib tug concentration ntawm 30% thaum them tag nrho. Cov kua qaub ntshiab muaj qhov ntom ntom ntawm 1.835 g / cm3 3, ib qho electrolyte yog li 1.300 g / cm 3. Thaum lub roj teeb tawm, cov tshuaj electrochemical tshwm sim nyob rau hauv nws, raws li ib tug tshwm sim ntawm cov sulfuric acid yog npaum li cas los ntawm cov electrolyte. Qhov ceev ntawm cov tshuaj concentration nyob ntawm yuav luag proportionally, yog li nws yuav tsum tau txo vim qhov txo qis hauv cov electrolyte concentration.
Ntev npaum li qhov tso tawm tam sim no ntws los ntawm lub roj teeb, cov kua qaub ze ntawm nws cov electrodes tau nquag siv, thiab cov electrolyte ua ntau thiab ntau dua. Diffusion ntawm cov kua qaub los ntawm qhov ntim ntawm tag nrho cov electrolyte thiab rau cov electrode daim hlau tuav ib tug kwv yees li qhov siv ntawm cov tshuaj tiv thaiv thiab, vim li ntawd, cov zis.voltage.
Thaum pib ntawm cov txheej txheem tso tawm, kev nthuav tawm ntawm cov kua qaub los ntawm cov electrolyte mus rau hauv daim hlau tshwm sim sai vim tias qhov tshwm sim sulfate tseem tsis tau txhaws lub qhov hws hauv cov khoom siv ntawm cov electrodes. Raws li sulfate pib tsim thiab sau cov pores ntawm electrodes, diffusion tshwm sim qeeb dua.
Txoj kev xav, koj tuaj yeem txuas ntxiv qhov tso tawm kom txog thaum tag nrho cov kua qaub siv thiab cov electrolyte yog dej ntshiab. Txawm li cas los xij, kev paub qhia tau hais tias kev tso tawm yuav tsum tsis txhob txuas ntxiv tom qab qhov ceev ntawm electrolyte tau poob mus rau 1.150 g / cm33.
Thaum qhov ceev poob ntawm 1, 300 mus rau 1, 150, qhov no txhais tau hais tias ntau sulfate tau tsim thaum lub sij hawm cov tshuaj tiv thaiv, thiab nws puv tag nrho cov pores nyob rau hauv lub active khoom ntawm daim hlau, i.e. yuav luag tag nrho cov sulfuric acid. Qhov ceev yog nyob ntawm qhov concentration proportionally, thiab tib yam li cov roj teeb nqi nyob ntawm qhov ceev. Ntawm daim duab. Qhov kev cia siab ntawm cov roj teeb them rau ntawm electrolyte ntom yog qhia hauv qab no.
Hloov qhov ceev ntawm cov electrolyte yog qhov zoo tshaj plaws txhais tau tias ntawm kev txiav txim siab lub xeev ntawm kev tso tawm ntawm lub roj teeb, muab nws siv kom zoo.
Degrees ntawm paug ntawm lub tsheb roj teeb nyob ntawm qhov ceev ntawm cov electrolyte
Nws qhov ceev yuav tsum ntsuas txhua ob lub lis piam thiab cov ntawv nyeem yuav tsum tau sau tseg tsis tu ncua rau yav tom ntej siv.
Lub denser cov electrolyte, cov kua qaub ntau nws muaj, thiab lub roj teeb ntau dua. Qhov ceev hauv 1.300-1.280g / cm 3qhia tag nrho cov nqi. Raws li txoj cai, cov qib hauv qab no ntawm cov roj teeb tawm tau txawv nyob ntawm qhov ceev ntawm electrolyte:
- 1, 300-1, 280 - tag nrho them:
- 1, 280-1, 200 - ntau tshaj ib nrab khoob;
- 1, 200-1, 150 - tsawg dua ib nrab puv;
- 1, 150 - yuav luag tas.
Lub roj teeb uas them tag nrho muaj qhov hluav taws xob ntawm 2.5 txog 2.7 volts ntawm ib lub xov tooj ua ntej txuas nrog nws lub tsheb loj, sai li sai tau raws li kev thauj khoom sib txuas, qhov hluav taws xob sai poob mus txog 2.1 volts hauv peb lossis plaub feeb. Qhov no yog vim qhov tsim ntawm ib txheej nyias ntawm cov hlau lead sulfate nyob rau saum npoo ntawm cov hlau tsis zoo electrode thiab nruab nrab ntawm cov hmoov txhuas peroxide thiab cov hlau ntawm cov hlau zoo. Tus nqi kawg ntawm lub xov tooj ntawm tes tom qab txuas rau lub tsheb network yog li 2.15-2.18 volts.
Thaum lub sijhawm tam sim no pib ntws los ntawm lub roj teeb thaum thawj teev ntawm kev ua haujlwm, muaj qhov hluav taws xob poob mus rau 2 V, vim qhov nce ntxiv hauv kev tiv thaiv sab hauv ntawm lub hlwb vim yog tsim cov sulfate ntau dua, uas ua rau muaj kev cuam tshuam ntau ntxiv. lub pores ntawm daim hlau, thiab tshem tawm cov kua qaub los ntawm electrolyte. Tsis ntev ua ntej pib ntawm cov dej ntws tam sim no, qhov ceev ntawm cov electrolyte yog siab tshaj plaws thiab sib npaug rau 1.300 g / cm3. Thaum xub thawj, nws qhov tsis tshua muaj tshwm sim sai sai, tab sis tom qab ntawd lub xeev sib npaug yog tsim los ntawm qhov ntom ntom ntawm cov kua qaub ze ntawm daim hlau thiab hauv cov ntim loj ntawm cov electrolyte, kev tshem tawm cov kua qaub los ntawm cov electrodes yog txhawb los ntawm cov khoom ntawm cov khoom tshiab. acid los ntawm qhov tseem ceeb ntawm cov electrolyte. Hauv qhov no, qhov nruab nrab ntom ntom ntawm cov electrolytetxuas ntxiv mus tsis tu ncua raws li kev vam meej hauv daim duab. siab dua. Tom qab thawj zaug poob, qhov hluav taws xob txo qis qis dua, tus nqi qis dua nyob ntawm qhov load ntawm lub roj teeb. Lub sijhawm teeb tsa ntawm cov txheej txheem tso tawm yog qhia hauv daim duab. hauv qab no.
Saib xyuas lub xeev ntawm cov electrolyte hauv lub roj teeb
Ib lub hydrometer yog siv los txiav txim qhov ntom. Nws muaj ib lub khob ntim me me uas muaj qhov nthuav dav ntawm qhov kawg uas muaj kev txhaj tshuaj lossis mercury thiab ib qho kev kawm tiav ntawm qhov kawg. Qhov ntsuas no tau sau los ntawm 1.100 txog 1.300 nrog ntau yam txiaj ntsig nyob nruab nrab, raws li qhia hauv daim duab. hauv qab no. Yog tias qhov hydrometer no tau muab tso rau hauv ib qho electrolyte, nws yuav tog rau qhov tob. Thaum ua li ntawd, nws yuav tshem tawm qee qhov ntim ntawm electrolyte, thiab thaum qhov sib npaug ntawm txoj haujlwm mus txog, qhov hnyav ntawm qhov hloov pauv yuav tsuas yog sib npaug ntawm qhov hnyav ntawm hydrometer. Txij li qhov ceev ntawm cov electrolyte yog sib npaug rau qhov sib piv ntawm nws qhov hnyav rau ntim, thiab qhov hnyav ntawm hydrometer paub, txhua qib ntawm nws cov immersion nyob rau hauv cov tshuaj sib haum mus rau ib tug tej yam ceev.
Qee lub hydrometers tsis muaj qhov ntsuas nrog qhov ntsuas qhov ntom ntom, tab sis tau cim nrog cov ntawv sau: "Chaw them", "Ib nrab tawm", "Tag nrho tawm" lossis zoo sib xws.
