Cov khoom redox ntawm ib tus neeg atoms nrog rau ions yog qhov teeb meem tseem ceeb hauv chemistry niaj hnub no. Cov khoom no pab piav qhia txog kev ua haujlwm ntawm cov khoom thiab cov khoom, ua kom muaj kev sib piv ntawm cov tshuaj lom neeg ntawm cov atoms sib txawv.
Tus neeg sawv cev oxidizing yog dab tsi
Ntau txoj haujlwm hauv chemistry, suav nrog cov lus nug rau kev sib koom ua ke hauv xeev hauv qib 11, thiab OGE hauv qib 9, cuam tshuam nrog lub tswv yim no. Tus neeg sawv cev oxidizing yog suav tias yog atoms lossis ions uas, nyob rau hauv cov txheej txheem ntawm kev sib cuam tshuam tshuaj, txais electrons los ntawm lwm ion lossis atom. Yog hais tias peb tsom xam cov oxidizing zog ntawm atoms, peb xav tau lub periodic system ntawm Mendeleev. Nyob rau hauv lub sij hawm nyob rau hauv lub rooj ntawm sab laug mus rau sab xis, lub peev xwm oxidizing ntawm atoms nce, uas yog, nws hloov zoo ib yam li cov khoom uas tsis yog-hlau. Nyob rau hauv subgroups tseem ceeb, qhov parameter no txo qis los ntawm sab saum toj mus rau hauv qab. Ntawm cov khoom yooj yim tshaj plaws uas muaj peev xwm oxidizing, fluorine yog nyob rau hauv cov hlau lead. Ib lo lus xws li "electronegativity", uas yog, lub peev xwm ntawm lub atom coj mus rau hauv cov ntaub ntawv ntawm kev sib tshuam tshuaj.electrons, tuaj yeem suav hais tias yog cov khoom siv oxidizing. Ntawm cov tshuaj complex uas muaj ob los yog ntau yam tshuaj ntsiab lus, ci oxidizing tus neeg sawv cev yuav suav hais tias: poov tshuaj permanganate, poov tshuaj chlorate, ozone.
Tus neeg txo qis yog dab tsi
Qhov txo qis ntawm atoms yog yam ntxwv ntawm cov khoom yooj yim uas nthuav tawm cov khoom siv hlau. Nyob rau hauv lub periodic table, metallic zog tsis muaj zog los ntawm sab laug mus rau sab xis nyob rau hauv lub sij hawm, thiab nyob rau hauv lub ntsiab subgroups (vertically) lawv nce. Qhov tseem ceeb ntawm kev rov qab los yog rov qab los ntawm cov hluav taws xob, uas nyob rau sab nraud ntawm lub zog. Qhov ntau dua ntawm cov plhaub hluav taws xob (theem), qhov yooj yim dua nws yog muab "ntxiv" electrons thaum lub sij hawm tshuaj lom neeg.
Cov khoom siv (alkaline, alkaline-lub ntiaj teb) hlau muaj cov khoom zoo heev. Tsis tas li ntawd, cov khoom uas muaj qhov zoo sib xws, peb qhia txog cov sulfur oxide (6), carbon monoxide. Txhawm rau kom tau txais qhov siab tshaj plaws oxidation lub xeev, cov tebchaw no raug yuam kom pom cov khoom txo qis.
txheej txheem oxidation
Yog thaum muaj kev sib cuam tshuam tshuaj lom neeg lub atom lossis ib qho ion muab electrons rau lwm lub atom (ion), peb tab tom tham txog cov txheej txheem ntawm oxidation. Txhawm rau txheeb xyuas seb yuav txo cov khoom thiab oxidizing lub zog hloov pauv li cas, koj yuav xav tau cov lus ntu ntu ntawm cov ntsiab lus, nrog rau kev paub txog cov kev cai niaj hnub ntawm physics.
txheej txheem rov ua dua
Txo cov txheej txheem cuam tshuam nrog kev lees paub los ntawm ions ntawm ob qho tib siatoms ntawm electrons los ntawm lwm cov atoms (ions) thaum lub sij hawm ncaj qha tshuaj. Cov tshuaj tiv thaiv zoo tshaj plaws yog nitrites, sulfites ntawm alkali hlau. Cov khoom txo qis hauv cov txheej txheem ntawm cov ntsiab lus hloov zoo ib yam li cov khoom siv hlau ntawm cov khoom yooj yim.
OVR Parsing Algorithm
Yuav kom cov tub ntxhais kawm tso cov coefficients nyob rau hauv cov tshuaj tiv thaiv tiav, nws yog ib qho tsim nyog yuav tau siv cov algorithm tshwj xeeb. Redox cov khoom kuj tseem pab daws cov teeb meem kev suav ntau yam hauv kev txheeb xyuas, cov organic, thiab cov chemistry. Peb qhia qhov kev txiav txim ntawm kev txheeb xyuas cov tshuaj tiv thaiv:
- Ua ntej, nws yog ib qho tseem ceeb rau kev txiav txim siab oxidation lub xeev ntawm txhua yam khoom siv uas siv cov cai.
- Tom ntej no, cov atoms lossis ions uas tau hloov lawv lub xeev oxidation tau txiav txim siab koom nrog cov tshuaj tiv thaiv.
- Cov cim rho tawm thiab cov cim ntxiv qhia cov lej ntawm cov hluav taws xob dawb muab thiab tau txais thaum muaj tshuaj lom neeg.
- Tom ntej no, ntawm tus naj npawb ntawm tag nrho cov electrons, qhov tsawg kawg nkaus ntau ntau yog txiav txim siab, uas yog, tus lej uas muab faib tsis muaj qhov seem los ntawm qhov tau txais thiab muab electrons.
- Tom qab ntawd nws muab faib ua cov electrons koom nrog cov tshuaj tiv thaiv.
- Tom ntej no, peb txiav txim siab seb cov ions lossis atoms twg muaj cov khoom txo qis, thiab tseem txiav txim siab oxidizing tus neeg sawv cev.
- Thaum kawg muab cov coefficients hauv qhov sib npaug.
Siv txoj kev tshuav nyiaj li cas hauv hluav taws xob, cia peb tso cov coefficients hauv cov tswv yim tshuaj tiv thaiv no:
NaMnO4 + hydrogen sulfide + sulfuric acid=S + Mn SO4 +…+…
Algorithm rau kev daws qhov teeb meem
Cia saib seb cov tshuaj twg yuav tsum tsim tom qab kev sib cuam tshuam. Txij li thaum twb muaj tus neeg sawv cev oxidizing nyob rau hauv cov tshuaj tiv thaiv (nws yuav yog manganese) thiab txo tus neeg sawv cev (nws yuav yog leej faj), cov tshuaj raug tsim nyob rau hauv uas lub xeev oxidation tsis hloov lawm. Txij li thaum cov tshuaj tiv thaiv tseem ceeb tshwm sim ntawm cov ntsev thiab cov kua qaub uas muaj zog oxygen, ib qho ntawm cov khoom kawg yuav yog dej, thiab qhov thib ob yuav yog sodium ntsev, ntau meej, sodium sulfate.
Tam sim no cia peb ua ib lub tswv yim rau muab thiab txais electrons:
- Mn+7 takes 5 e=Mn+2.
Second part of the scheme:
- S-2 gives2e=S0
Peb muab cov coefficients tso rau hauv qhov kev tshwm sim thawj zaug, tsis txhob hnov qab suav tag nrho cov sulfur atoms hauv qhov sib npaug.
2NaMnO4 + 5H2S + 3H2SO 4 =5S + 2MnSO4 + 8H2O + Na2SO 4.
Kev tshuaj xyuas OVR cuam tshuam nrog hydrogen peroxide
Siv OVR parsing algorithm, peb tuaj yeem sau ib qho kev sib npaug rau cov tshuaj tiv thaiv tsis tu ncua:
hydrogen peroxide + sulfuric acid + poov tshuaj permagnanate=Mn SO4 + oxygen + …+…
Lub xeev oxidation hloov cov pa oxygen ion (hauv hydrogen peroxide) thiab manganese cation hauv poov tshuaj permanganate. Ntawd yog, peb muaj tus neeg sawv cev txo qis, nrog rau tus neeg sawv cev oxidizing.
Cia peb txiav txim siab seb yam tshuaj twg tseem tuaj yeem tau txais tom qab kev sib cuam tshuam. Ib qho ntawm lawv yuav yog dej, uas yog qhov pom tseeb heev ntawm cov kua qaub thiab ntsev. Potassium tsis tsim ib qho tshiabCov tshuaj, cov khoom thib ob yuav yog cov ntsev ntsev, uas yog sulfate, txij li cov tshuaj tiv thaiv nrog sulfuric acid.
Scheme:
2O - pub 2 electrons thiab hloov mus ua O 2 0 5
Mn+7 lees 5 electrons thiab dhau los ua Mn ion+2 2
Tsim cov coefficients.
5H2O2 + 3H2SO4 + 2KMnO4=5O2 + 2Mn SO4 + 8H 2O + K2SO4
Piv txwv ntawm OVR tsom xam nrog cov poov tshuaj chromate
Siv txoj kev sib npaug hluav taws xob, peb yuav ua qhov sib npaug nrog cov coefficients:
FeCl2 + hydrochloric acid + potassium chromate=FeCl3+ CrCl3 + …+…
Oxidation xeev hloov hlau (hauv ferric chloride II) thiab chromium ion hauv potassium dichromate.
Tam sim no cia peb sim nrhiav seb lwm yam tshuaj dab tsi tsim. Ib qho tuaj yeem yog ntsev. Txij li thaum poov tshuaj tsis tsim ib qho kev sib xyaw, yog li ntawd, cov khoom thib ob yuav yog cov ntsev ntsev, ntau dua, cov tshuaj chloride, vim tias cov tshuaj tiv thaiv tau tshwm sim nrog hydrochloric acid.
Cia peb ua daim duab:
Fe+2 gives e= Fe+3 6 reducer,
2Cr+6 lees 6 e=2Cr +31 oxidizer.
Muab cov coefficients nyob rau hauv thawj qhov tshwm sim:
6K2Cr2O7+ FeCl2+ 14HCL=7H2O + 6FeCl3 + 2CrCl3 + 2KCl
Piv txwvOVR tsom xam nrog cov poov tshuaj iodide
Txoj kev cai, cia peb ua qhov sib npaug:
poov tshuaj permanganate + sulfuric acid + poov tshuaj iodide … manganese sulfate + iodine + … + …
Oxidation xeev hloov manganese thiab iodine. Ntawd yog, tus neeg sawv cev txo qis thiab tus neeg sawv cev oxidizing tam sim no.
Tam sim no cia saib seb peb yuav xaus li cas. Lub compound yuav nrog potassium, uas yog, peb yuav tau txais poov tshuaj sulfate.
Cov txheej txheem rov qab tshwm sim hauv iodine ions.
Cia peb kos ib qho kev hloov pauv hluav taws xob:
- Mn+7 lees 5 e=Mn+2 2 yog oxidant,
- 2I- give away 2 e=I2 05 yog tus txo tus neeg sawv cev.
Muab cov coefficients nyob rau hauv thawj cov tshuaj tiv thaiv, tsis txhob hnov qab sau tag nrho cov sulfur atoms nyob rau hauv qhov sib npaug.
210KI + KMnO4 + 8H2SO4 =2MnSO 4+ 5I2 + 6K2SO4 + 8H 2O
Piv txwv ntawm kev tshuaj xyuas ntawm OVR cuam tshuam nrog sodium sulfite
Siv cov txheej txheem classical, peb yuav tsim ib qho kev sib npaug rau lub voj voog:
- sulfuric acid + KMnO4 + sodium sulfite… sodium sulfate + manganese sulfate +…+…
Tom qab kev sib cuam tshuam peb tau txais ntsev ntsev, dej.
Cia peb ua daim duab:
- Mn+7 takes 5 e=Mn+2 2,
- S+4 muab 2 e=S+6 5.
Teem cov coefficients hauv cov tshuaj tiv thaiv raws li kev xav, tsis txhob hnov qab ntxiv cov sulfur atoms thaum npaj cov coefficients.
3H2SO4 + 2KMnO4 + 5Na2 SO3 =K2SO4+ 2MnSO4+ 5Na2 SO4+ 3H2O.
Piv txwv ntawm kev tshuaj xyuas ntawm OVR cuam tshuam nrog nitrogen
Cia li ua cov haujlwm hauv qab no. Siv cov algorithm, peb yuav ua kom tiav cov lus sib npaug:
- manganese nitrate + nitric acid + PbO2=HMnO4+Pb(NO3) 2+
Cia peb soj ntsuam seb cov tshuaj twg tseem tsim. Txij li thaum cov tshuaj tiv thaiv tau tshwm sim ntawm tus neeg sawv cev oxidizing muaj zog thiab ntsev, nws txhais tau tias cov khoom yuav yog dej.
Qhia qhov kev hloov pauv ntawm tus lej ntawm electrons:
- Mn+2 gives 5 e=Mn+7 2 nthuav tawm cov khoom ntawm tus neeg txo qis,
- Pb+4 takes 2 e=Pb+2 5 oxidizer.
3. Peb npaj cov coefficients nyob rau hauv thawj cov tshuaj tiv thaiv, nco ntsoov ntxiv tag nrho cov nitrogen muaj nyob rau sab laug ntawm tus thawj kab zauv:
- 2Mn(NO3)2 + 6HNO3 + 5PbO 2 =2HMnO4 + 5Pb(NO3)2 + 2H 2O.
Cov tshuaj tiv thaiv no tsis pom qhov txo qis ntawm nitrogen.
Thib ob redox tshuaj tiv thaiv nrog nitrogen:
Zn + sulfuric acid + HNO3=ZnSO4 + NO+…
- Zn0 muab 2 e=Zn+23 yuav rov qab,
N+5accepts 3 e=N+2 2 is an oxidizer.
Txhim cov coefficients hauv qhov muab tshuaj tiv thaiv:
3Zn + 3H2SO4 + 2HNO3 =3ZnSO 4 + 2NO + 4H2O.
Qhov tseem ceeb ntawm cov tshuaj tiv thaiv redox
Qhov kev txo qis nto moo tshaj plaws yog photosynthesis, uas yog yam ntxwv ntawm cov nroj tsuag. Restorative zog hloov li cas? Cov txheej txheem tshwm sim nyob rau hauv biosphere, ua rau kom muaj zog ntxiv nrog kev pab los ntawm ib qho chaw sab nraud. Nws yog lub zog no uas tib neeg siv rau nws cov kev xav tau. Ntawm cov piv txwv ntawm oxidative thiab txo cov tshuaj tiv thaiv cuam tshuam nrog cov tshuaj lom neeg, kev hloov pauv ntawm nitrogen, carbon, thiab oxygen compounds yog qhov tseem ceeb. Ua tsaug rau photosynthesis, lub ntiaj teb huab cua muaj xws li ib tug muaj pes tsawg leeg uas yog tsim nyog rau txoj kev loj hlob ntawm cov kab mob nyob. Ua tsaug rau photosynthesis, cov pa roj carbon dioxide nyob rau hauv lub plhaub huab cua tsis nce, lub ntiaj teb nto tsis overheat. Cov nroj tsuag tsis tsuas yog txhim kho nrog kev pab los ntawm cov tshuaj tiv thaiv redox, tab sis kuj tsim cov khoom xws li oxygen thiab qabzib uas tsim nyog rau tib neeg. Yog tsis muaj cov tshuaj tiv thaiv no, tag nrho lub voj voog ntawm cov khoom nyob rau hauv qhov tsis tuaj yeem ua tsis tau, nrog rau lub neej ntawm cov organic.
Kev siv tswv yim ntawm RIA
txhawm rau khaws cov hlau saum npoo av, koj yuav tsum paub tias cov hlau nquag muaj cov khoom siv kho dua tshiab, yog li koj tuaj yeem npog lub npoo nrog cov txheej txheem ntawm cov khoom siv ntau dua, thaum ua kom cov txheej txheem tshuaj corrosion. Vim muaj cov khoom siv redox, cov dej haus tau ntxuav thiab tua kab mob. Tsis muaj teeb meem daws tau yam tsis raug muab cov coefficients hauv qhov sib npaug. Yuav kom tsis txhob ua yuam kev, nws yog ib qho tseem ceeb kom muaj kev nkag siab txog tag nrho cov redoxparameters.
Tiv thaiv cov tshuaj corrosion
Corrosion yog ib qho teeb meem tshwj xeeb rau tib neeg lub neej thiab kev ua ub no. Raws li qhov tshwm sim ntawm kev hloov tshuaj lom neeg no, kev puas tsuaj ntawm cov hlau tshwm sim, qhov chaw ntawm lub tsheb, cov cuab yeej siv tshuab poob lawv cov yam ntxwv ua haujlwm. Txhawm rau kho qhov teeb meem no, kev tiv thaiv tread yog siv, hlau yog coated nrog ib txheej ntawm cov kua roj vanish lossis xim, thiab cov khoom siv los tiv thaiv corrosion. Piv txwv li, ib tug hlau nto yog them nrog ib txheej ntawm active hlau - txhuas.
Zoo kawg
Ntau yam kev rov qab los tshwm sim hauv tib neeg lub cev, ua kom lub cev ua haujlwm ntawm lub plab zom mov. Xws li cov txheej txheem hauv lub neej xws li fermentation, lwj, ua pa kuj cuam tshuam nrog cov khoom kho kom zoo. Txhua tus tsiaj nyob hauv peb lub ntiaj teb muaj peev xwm zoo sib xws. Yog tias tsis muaj kev cuam tshuam nrog kev xa rov qab thiab kev lees txais ntawm electrons, mining, kev tsim khoom ntawm ammonia, alkalis, thiab acids yog tsis yooj yim sua. Nyob rau hauv analytical chemistry, tag nrho cov txheej txheem ntawm volumetric tsom xam yog raws li meej ntawm cov txheej txheem redox. Kev sib ntaus tawm tsam qhov tshwm sim tsis zoo li tshuaj lom neeg corrosion kuj yog raws li kev paub txog cov txheej txheem no.
