Lub tsev kawm ntawv chemistry chav kawm yog ib qho kev qhia qhia txog kev kawm nyuaj. Txij thaum pib, cov tub ntxhais kawm sim nkag siab yuav ua li cas los daws cov teeb meem kev suav. Cia nyob rau hauv thawj theem lawv muaj me ntsis kev siv, tab sis yog hais tias ib tug me nyuam kawm ntawv tau kawm, piv txwv li, yuav ua li cas nrhiav tau lub loj ntawm cov tshuaj uas tau reacted, ces nws yuav zoo thov kev ua tau zoo.
Cia peb xav txog ib qho piv txwv yooj yim ntawm qhov teeb meem, raws li qhov peb tuaj yeem kawm los daws cov teeb meem nyuaj dua. Piv txwv tias nws coj koj 11.2 litres kom hlawv cov pa roj carbon monoxide (II). Koj tau txais pes tsawg grams ntawm CO2?
1. Sau cov lus sib npaug.
CO + O2=CO2
2. Sib npaug rau cov pa oxygen. Muaj ib txoj cai uas feem ntau tuaj yeem pab koj. Pib teeb cov coefficients los ntawm cov khoom ntawd, tus naj npawb ntawm cov atoms uas yog khib. Hauv qhov no, nws yog cov pa oxygen hauv CO molecule. Peb muab ib coefficient 2 rau nws, Txij li thaum ob carbon atoms raug tsim nyob rau sab laug, thiab ib tug ntawm sab xis, peb muab 2 nyob rau hauv pem hauv ntej ntawm CO2. Yog li, peb tau:
2CO + O2=2CO2
Raws li koj tuaj yeem pom, muaj plaub lub pa oxygen atom nyob rau sab laug thiab sab xis. Cov pa roj carbon kuj tseem nyob hauv qhov sib npaug. Yog li ntawd, sib npaugyog.
3. Tom ntej no, koj yuav tsum nrhiav tus nqi ntawm O2. Kev txiav txim siab qhov hnyav molecular rau cov menyuam kawm ntawv yog qhov nyuaj heev thiab tsis nco qab, yog li peb yuav siv lwm txoj hauv kev. Nco qab tias muaj molar ntim, uas yog sib npaug rau 22.4 l / mol. Koj yuav tsum nrhiav tau pes tsawg moles (n) reacted: n=V/V m. Hauv peb cov ntaub ntawv, n=0.5 mol.
4. Tam sim no cia peb ua ib feem. Cov pa oxygen uas tau nkag mus rau hauv cov tshuaj tiv thaiv yog ob zaug tsawg dua n (CO2). Qhov no ua raws li qhov tseeb tias 0.5 mol / 1=x mol / 2. Ib qho piv txwv yooj yim ntawm ob qhov ntau tau pab ua qhov sib npaug zoo. Thaum peb pom x=1, peb tuaj yeem tau txais cov lus teb rau lo lus nug ntawm yuav ua li cas thiaj nrhiav tau pawg.
5. Muaj tseeb, pib nrog, koj yuav tsum nco ntsoov ib qho ntxiv: m \u003d Mn. Qhov kawg hloov pauv tau pom, tab sis yuav ua li cas nrog M? Molar mass yog qhov kev sim ntsuas tus nqi txheeb ze rau hydrogen. Nws yog nws tus uas sau los ntawm tsab ntawv M. Tam sim no peb paub tias m (CO2) u003d 12 g / mol1 mol \u003d 12 g. Yog li peb tau txais cov lus teb. Raws li koj tau pom, tsis muaj dab tsi nyuab.
Txoj haujlwm no yooj yim heev piv rau ntau lwm tus. Txawm li cas los xij, qhov tseem ceeb yog kom nkag siab yuav ua li cas thiaj nrhiav tau qhov loj. Xav txog ib qho molecule ntawm qee yam khoom. Nws tau ntev tau paub tias mole muaj 610^23 molecules. Nyob rau tib lub sij hawm, nyob rau hauv lub Periodic system muaj ib tug tsim loj ntawm ib tug 1 mole. Qee zaum koj yuav tsum xam cov molar loj ntawm ib yam khoom. Piv txwv li M(H20)=18 grams/mol. Ntawd yog, ib qho hydrogen molecule muaj M=1 gram / mol. Tab sis dej muaj ob lub H atoms, tsis txhob hnov qabhais txog lub xub ntiag ntawm oxygen, uas muab rau peb ntxiv 16 grams. Piv txwv li, peb tau 18 grams / mol.
Kev suav lej suav yuav tom qab muaj kev siv tau. Tshwj xeeb tshaj yog rau cov tub ntxhais kawm uas xav tau kev cob qhia chemistry. Tsis txhob ntshai lo lus no yog tias koj kawm hauv ib lub tsev kawm ntawv tsis yog tub ntxhais kawm. Tab sis yog tias chemistry yog koj cov ntsiab lus tseem ceeb, nws zoo dua tsis txhob khiav cov ntsiab lus yooj yim. Yog li, tam sim no koj paub yuav ua li cas nrhiav cov pawg. Nco ntsoov tias hauv chemistry nws yog ib qho tseem ceeb heev uas yuav tsum tau ua ib tus neeg zoo sib xws thiab mloog zoo uas tsis yog tsuas yog paub qee cov algorithms xwb, tab sis kuj paub siv lawv li cas.
