Peb tau ntsib nrog ntau yam tshuaj lom neeg sib cuam tshuam. Lub combustion ntawm natural gas, rusting ntawm hlau, lub souring ntawm cov mis nyuj yog deb ntawm tag nrho cov txheej txheem uas tau kawm nyob rau hauv kom meej nyob rau hauv lub tsev kawm ntawv chemistry chav kawm.
Qee qhov kev tawm tsam siv cov feem ntawm cov vib nas this, thaum qee qhov kev sib cuam tshuam siv sijhawm ntau hnub lossis ntau lub lis piam.
Cia peb sim txheeb xyuas qhov kev cia siab ntawm cov tshuaj tiv thaiv tus nqi ntawm qhov kub, qhov siab, thiab lwm yam. Hauv cov qauv kev kawm tshiab, qhov tsawg kawg nkaus ntawm lub sijhawm kawm raug faib rau qhov teeb meem no. Nyob rau hauv cov kev ntsuam xyuas ntawm kev sib koom ua ke hauv lub xeev kev kuaj mob, muaj cov dej num ntawm kev vam khom ntawm cov tshuaj tiv thaiv tus nqi ntawm qhov kub thiab txias, concentration, thiab txawm tias cov dej num suav nrog. Ntau tus tub ntxhais kawm theem siab tau ntsib qee yam nyuaj hauv kev nrhiav cov lus teb rau cov lus nug no, yog li peb yuav txheeb xyuas cov ncauj lus kom ntxaws.
Kev cuam tshuam ntawm qhov teeb meem hauv kev txiav txim siab
Cov ntaub ntawv hais txog tus nqi tshuaj tiv thaiv yog qhov ua tau zoo thiab kev tshawb fawb tseem ceeb. Piv txwv li, nyob rau hauv ib tug tshwj xeeb zus tau tej cov tshuaj thiab cov khoom los ntawm ib tug muabtus nqi ncaj qha nyob ntawm qhov ua tau zoo ntawm cov khoom siv, tus nqi ntawm cov khoom.
Kev faib tawm ntawm kev tawm tsam tsis tu ncua
Nws muaj kev sib raug zoo ntawm lub xeev ntawm kev sib sau ua ke ntawm cov khoom pib thiab cov khoom tsim thaum lub sij hawm cov txheej txheem tshuaj: heterogeneous interactions.
Ib feem ntau nkag siab hauv chemistry ua ib yam khoom lossis sib xyaw ua ke.
Ib homogeneous system yog ib qho uas muaj ib theem (ib lub xeev ntawm kev sib sau). Ua piv txwv, peb tuaj yeem hais txog kev sib xyaw ntawm cov pa roj, ntau cov kua sib txawv.
Heterogeneous yog ib qho system uas reactants nyob rau hauv daim ntawv ntawm gases thiab kua, solids thiab gases.
Tsis yog tsuas yog kev vam khom ntawm cov tshuaj tiv thaiv tus nqi ntawm qhov kub thiab txias, tab sis kuj yog nyob rau theem ntawm cov khoom siv hauv kev txheeb xyuas kev sib cuam tshuam.
Ib homogeneous muaj pes tsawg leeg yog tus cwj pwm los ntawm kev ntws ntawm cov txheej txheem thoob plaws hauv lub ntim, uas txhim kho nws qhov zoo.
Yog tias cov tshuaj thawj zaug nyob hauv cov xeev sib txawv, hauv qhov no, kev sib cuam tshuam ntau tshaj plaws tau pom nyob rau ntawm theem ciam teb. Piv txwv li, thaum lub active hlau yog yaj nyob rau hauv ib tug acid, qhov tsim ntawm ib yam khoom (ntsev) yog pom tsuas yog nyob rau saum npoo ntawm lawv kev sib cuag.
Kev sib raug zoo ntawm lej ntawm cov txheej txheem ceev thiab ntau yam
Qhov sib npaug ntawm cov tshuaj tiv thaiv tshuaj tiv thaiv qhov ntsuas kub zoo li cas? Rau ib homogeneous txheej txheem, tus nqi yog txiav txim los ntawm tus nqiib yam khoom uas cuam tshuam los yog tsim thaum lub sij hawm cov tshuaj tiv thaiv nyob rau hauv lub ntim ntawm lub system ib chav tsev ntawm lub sij hawm.
Rau cov txheej txheem heterogeneous, tus nqi txiav txim los ntawm tus nqi ntawm cov tshuaj reacting los yog tsim nyob rau hauv cov txheej txheem ib chav tsev rau ib tug tsawg kawg nkaus lub sij hawm ntawm lub sij hawm.
Yam cuam tshuam rau tus nqi ntawm cov tshuaj tiv thaiv tshuaj
Qhov xwm txheej ntawm cov tshuaj reacting yog ib qho laj thawj rau cov txheej txheem sib txawv. Piv txwv li, alkali hlau tsim alkalis nrog dej ntawm chav tsev kub, thiab cov txheej txheem yog nrog los ntawm khaus evolution ntawm gaseous hydrogen. Noble hlau (kub, platinum, nyiaj) tsis muaj peev xwm ntawm cov txheej txheem xws li nyob rau hauv chav tsev kub los yog thaum rhuab.
Qhov xwm txheej ntawm cov tshuaj reactants yog qhov tseem ceeb uas tau coj los rau hauv kev lag luam tshuaj lom neeg txhawm rau txhawm rau nce cov txiaj ntsig ntawm kev tsim khoom.
Kev sib raug zoo ntawm cov concentration ntawm reagents thiab ceev ntawm cov tshuaj tiv thaiv tshuaj tau raug qhia. Qhov siab dua, cov khoom ntau dua yuav sib tsoo, yog li, cov txheej txheem yuav ua sai dua.
Txoj cai ntawm kev txiav txim ntawm pawg neeg hauv daim ntawv lej piav qhia ncaj qha kev sib raug zoo ntawm cov concentration ntawm cov khoom pib thiab qhov ceev ntawm cov txheej txheem.
Nws tau tsim nyob rau hauv nruab nrab ntawm lub xyoo pua puv 19 los ntawm Lavxias teb sab chemist N. N. Beketov. Rau txhua tus txheej txheem, cov tshuaj tiv thaiv tsis tu ncua yog txiav txim siab, uas tsis cuam tshuam txog qhov kub thiab txias, concentration, lossis qhov xwm txheej ntawm cov reactants.
Tautxhawm rau txhawm rau ua kom cov tshuaj tiv thaiv nrog cov khoom, koj yuav tsum tau zom nws mus rau hmoov.
Nyob rau hauv rooj plaub no, thaj chaw saum npoo nce, uas muaj txiaj ntsig zoo rau kev ceev ntawm cov txheej txheem. Rau cov roj diesel, ib qho kev txhaj tshuaj tshwj xeeb yog siv, vim tias, thaum nws los rau hauv kev sib cuag nrog huab cua, tus nqi ntawm combustion ntawm ib tug sib tov ntawm hydrocarbons nce ho.
Qhov kev vam khom ntawm tus nqi ntawm cov tshuaj tiv thaiv ntawm qhov kub thiab txias tau piav qhia los ntawm molecular kinetic txoj kev xav. Nws tso cai rau koj los xam tus naj npawb ntawm kev sib tsoo ntawm cov molecules ntawm cov reagents nyob rau hauv tej yam kev mob. Armed nrog cov ntaub ntawv no, nyob rau hauv ib txwm muaj xwm txheej, tag nrho cov txheej txheem yuav tsum ua tam sim ntawd.
Tab sis yog tias peb xav txog ib qho piv txwv tshwj xeeb ntawm kev vam khom ntawm qhov ntsuas kub ntawm qhov ntsuas kub, nws hloov tawm tias rau kev sib cuam tshuam nws yog ib qho tsim nyog yuav tsum ua ntej rhuav tshem cov tshuaj sib txuas ntawm cov atoms txhawm rau tsim cov tshuaj tshiab los ntawm lawv. Qhov no yuav tsum muaj lub zog loj. Dab tsi yog qhov dependence ntawm cov tshuaj tiv thaiv ntawm qhov kub thiab txias? Lub zog ua kom txiav txim siab qhov muaj peev xwm ntawm kev tawg ntawm cov molecules, nws characterizes qhov tseeb ntawm cov txheej txheem. Nws units yog kJ/mol.
Yog lub zog tsis txaus, kev sib tsoo yuav tsis ua haujlwm, yog li nws tsis tuaj yeem nrog kev tsim cov molecule tshiab.
duab sawv cev
Qhov kev vam khom ntawm tus nqi ntawm cov tshuaj tiv thaiv ntawm qhov kub thiab txias tuaj yeem sawv cev rau cov duab. Thaum rhuab, tus naj npawb ntawm kev sib tsoo ntawm cov khoom nce, uas ua rau kom nrawm ntawm kev sib cuam tshuam.
Tus nqi tshuaj tiv thaiv piv rau qhov ntsuas kub zoo li cas? Lub zog ntawm molecules yog plotted horizontally, thiab tus naj npawb ntawm hais nrog ib tug siab zog cia yog qhia vertically. Daim duab yog qhov nkhaus uas siv tau los txiav txim qhov nrawm ntawm kev sib cuam tshuam.
Qhov ntau dua qhov sib txawv ntawm lub zog ntawm qhov nruab nrab, qhov deb ntawm qhov nkhaus yog los ntawm qhov siab tshaj plaws, thiab feem pua me me ntawm cov molecules muaj xws li lub zog cia.
yam tseem ceeb
Nws puas tuaj yeem sau qhov sib npaug rau qhov kev vam khom ntawm cov tshuaj tiv thaiv tus nqi tas li ntawm qhov kub thiab txias? Nws qhov kev nce ntxiv yog cuam tshuam nrog kev nce hauv cov txheej txheem ceev. Xws li ib qho kev vam khom yog tus yam ntxwv ntawm tus nqi, hu ua qhov kub thiab txias coefficient ntawm tus txheej txheem tus nqi.
Rau txhua qhov kev sib cuam tshuam, qhov kev vam khom ntawm cov tshuaj tiv thaiv tus nqi tas li ntawm qhov kub thiab txias tau tshwm sim. Yog tias nws nce 10 degrees, cov txheej txheem nrawm nce 2-4 zaug.
Kev nyob ntawm tus nqi ntawm homogeneous cov tshuaj tiv thaiv ntawm qhov kub thiab txias tuaj yeem sawv cev rau hauv daim ntawv lej.
Rau feem ntau ntawm kev sib cuam tshuam ntawm chav tsev kub, cov coefficient yog nyob rau hauv thaj tsam ntawm 2 txog 4. Piv txwv li, nrog rau qhov kub thiab txias coefficient ntawm 2.9, qhov kub thiab txias nce ntawm 100 degrees ua rau cov txheej txheem yuav luag 50,000 zaug.
Kev nyob ntawm cov tshuaj tiv thaiv tus nqi ntawm qhov kub thiab txias tuaj yeem piav qhia yooj yim los ntawm cov nqi sib txawv ntawm kev ua kom lub zog. Nws muaj qhov tsawg kawg nkaus ntawm cov txheej txheem ionic, uas tsuas yog txiav txim siab los ntawm kev sib cuam tshuam ntawm cations thiab anions. Ntau qhov kev sim ua pov thawj rau qhov tshwm sim tam sim ntawd ntawm cov tshuaj tiv thaiv.
Thaum lub zog ua kom siab siab, tsuas yog qee qhov kev sib tsoo me me ntawm cov khoom yuav ua rau muaj kev sib cuam tshuam. Nrog rau qhov nruab nrab ua kom lub zog, cov reactants yuav cuam tshuam ntawm qhov nruab nrab ceev.
Kev ua haujlwm ntawm kev vam khom ntawm cov tshuaj tiv thaiv tus nqi ntawm qhov siab thiab qhov kub thiab txias tsuas yog txiav txim siab tsuas yog nyob rau qib siab ntawm kev kawm, feem ntau ua rau muaj teeb meem loj rau menyuam yaus.
ntsuas qhov nrawm ntawm tus txheej txheem
Cov txheej txheem uas xav tau lub zog ua kom muaj zog tseem ceeb cuam tshuam nrog kev pib tawg lossis ua kom tsis muaj zog ntawm daim ntawv cog lus ntawm atoms hauv cov khoom qub. Nyob rau hauv cov ntaub ntawv no, lawv dhau mus rau ib tug tej yam intermediate xeev, hu ua lub activated complex. Nws yog lub xeev tsis ruaj khov, sai sai rau hauv cov khoom siv tshuaj tiv thaiv, cov txheej txheem yog nrog los ntawm kev tso tawm ntawm lub zog ntxiv.
Nyob hauv nws daim ntawv yooj yim tshaj plaws, lub tshuab ua kom muaj zog yog kev teeb tsa ntawm cov atoms nrog cov nyiaj qub uas tsis muaj zog.
Inhibitors thiab catalysts
Cia peb txheeb xyuas qhov kev cia siab ntawm cov tshuaj tiv thaiv enzymatic ntawm qhov nruab nrab kub. Cov tshuaj no ua raws li cov acceleratorstxheej txheem.
Lawv lawv tus kheej tsis yog koom nrog kev sib cuam tshuam, lawv tus lej tom qab ua tiav cov txheej txheem tseem tsis hloov pauv. Yog tias cov catalysts nce cov tshuaj tiv thaiv, ces inhibitors, ntawm qhov tsis sib xws, qeeb cov txheej txheem no.
Lub ntsiab lus ntawm qhov no yog qhov tsim ntawm cov sib xyaw nruab nrab, vim tias qhov kev hloov pauv ntawm cov txheej txheem ceev tau pom.
Zoo kawg
Ntau yam tshuaj sib cuam tshuam tshwm sim txhua feeb hauv ntiaj teb. Yuav ua li cas los tsim kom tau qhov dependence ntawm cov tshuaj tiv thaiv tus nqi ntawm kub? Qhov sib npaug Arrhenius yog kev piav qhia lej ntawm kev sib raug zoo ntawm tus nqi tas li thiab qhov kub thiab txias. Nws muab lub tswv yim ntawm cov txiaj ntsig ntawm kev ua kom lub zog ntawm qhov kev puas tsuaj los yog ua kom tsis muaj zog ntawm cov ntawv cog lus ntawm cov atoms hauv cov molecules, kev faib cov khoom rau hauv cov tshuaj tshiab yog ua tau.
Ua tsaug rau txoj kev xav ntawm molecular-kinetic, nws muaj peev xwm kwv yees qhov tshwm sim ntawm kev cuam tshuam ntawm cov khoom pib, los xam tus nqi ntawm cov txheej txheem. Ntawm cov xwm txheej uas cuam tshuam rau tus nqi tshuaj tiv thaiv, tshwj xeeb yog qhov tseem ceeb yog qhov hloov pauv ntawm qhov ntsuas kub, qhov feem pua ntawm cov khoom sib cuam tshuam, thaj chaw sib cuag, muaj cov catalyst (inhibitor), nrog rau qhov xwm txheej ntawm cov khoom sib cuam tshuam..
