Qhov sib txawv tseem ceeb ntawm qhov ntsuas qhov ntev thiab stoichiometry yog qhov ntsuas qhov ntev yog qhov hloov pauv ntawm tus nqi hauv ib chav mus rau tus nqi sib thooj hauv chav xav tau siv ntau yam hloov pauv thaum stoichiometry koom nrog kev sib raug zoo ntawm cov tshuaj reactants thiab / lossis cov khoom hauv Cov tshuaj tiv thaiv tshuaj los txiav txim seb cov ntaub ntawv xav tau ntau npaum li cas.
Lub sij hawm tsom xam qhov ntev yog qhov tseem ceeb hauv kev tshawb fawb, feem ntau hauv kev ua physics. Stoichiometry, ntawm qhov tod tes, yog qhov tseem ceeb hauv chemistry, hais txog tshuaj lom neeg. Siv stoichiometry, peb tuaj yeem txiav txim siab npaum li cas reactant reacted muab ntau npaum li cas ntawm cov khoom.
Dimensional Analysis yog dab tsi?
Dimensional tsom xam yog qhov hloov dua siab tshiab ntawm tus nqi hauv ib chav mus rau tus nqi sib thooj hauv chav tsev xav tau siv ntau yam hloov pauv. Ntxiv mus, lub hauv paus txoj kev xav tom qab no yog tias lub cev muaj pes tsawg leeg ntawm tib yam muaj tib qhov ntev. Yog li ntawd, peb tuaj yeem sib piv ib pawg ntawm lub cev nrog rau lwm cov khoom ntawm lub cev muaj qhov sib npaug. Piv txwv li, qhov ntev yog qhov ntau ntawm lub cev. Yog hais tias nws muab nyob rau hauv meters, peb muaj peev xwm muab piv nrog rau lwm qhov ntev txawm hais tias nws muab nyob rau hauv yards los yog mais. Peb tuaj yeem ua qhov kev sib piv no los ntawm kev hloov cov meters rau hauv yards lossis vice versa. Txawm li cas los xij, yog tias qhov ntau ntawm lub cev tsis muaj qhov sib npaug, peb tsis tuaj yeem sib piv lawv. Piv txwv li, peb tsis tuaj yeem piv qhov ntev nrog qhov loj vim tias lawv muaj qhov sib txawv.
Stoichiometry yog dab tsi?
Stoichiometry yog qhov kev sib raug zoo ntau lossis qhov sib piv ntawm ob lossis ntau yam khoom uas tau hloov pauv lub cev lossis tshuaj hloov pauv. Hauv lub tswv yim no, peb feem ntau cuam tshuam nrog huab hwm coj, ntim thiab moles ntawm cov khoom. Tsis tas li ntawd, kev siv lub tswv yim no yog raws li hauv qab no:
- Sib npaug tshuaj sib npaug
- Hloov cov grams rau moles, vice versa
- Xaiv molar pawg ntawm cov khoom tsis paub
- Xaiv molar piv ntawm cov tshuaj tiv thaiv
Cia peb xav txog ib qho piv txwv kom nkag siab txog lub tswv yim no. Rau cov tshuaj tiv thaiv A + 3B ⟶ C, reactants yog A thiab B, uas muab C ua khoom. Ntawm no, 3 molecules ntawm B yuav tsum hnov mob nrog ib lub molecule ntawm A kom muab ib lub molecule ntawm C. Qhov no yog qhov kev sib raug zoo ntawm stoichiometric ntawm cov reactants thiab cov khoom. Ntxiv mus, yog tias peb paub tus nqi ntawm A reactant reacted nrog B reactant muab C, peb tuaj yeem pom ntau npaum li cas ntawm B reactant peb xav tau rau cov tshuaj tiv thaiv no. Piv txwv li, yog tias 10.0 grams ntawm A reacted tag nrho nrog ib co npaum li cas ntawm B muab C, ces peb yuav tsum nrhiav tus naj npawb ntawm moles ntawm A reacted kom peb thiaj li nrhiav tau cov B uas reacted nrog A (hauv moles). Tom qab ntawd, peb tuaj yeem pom qhov loj ntawm B siv cov molecular loj ntawm B, siv cov kab zauv hauv qab no;
n=m/M
qhov twg n yog tus lej ntawm moles, m yog qhov hnyav, thiab M yog molecular mass ntawm reactant.
Qhov txawv ntawm Dimensional Analysis thiab Stoichiometry yog dab tsi?
Dimensional analysis tseem ceeb heev hauv physics, thaum stoichiometry tseem ceeb hauv chemistry. Qhov sib txawv tseem ceeb ntawm qhov ntsuas qhov ntev thiab stoichiometry yog qhov ntsuas qhov loj me yog qhov hloov pauv ntawm tus nqi hauv ib chav mus rau qhov sib npaug ntawm qhov xav tau ntawm chav tsev uas siv ntau yam kev hloov pauv thaum stoichiometry suav nrog kev sib raug zoo ntawm cov tshuaj reactants thiab / lossis cov khoom hauv cov tshuaj tiv thaiv tshuaj los txiav txim. xav kom muaj nuj nqis. Thaum xav txog cov kev xav hauv qab ntawm txhua lub tswv yim, txoj kev xav tom qab qhov kev tsom xam yog tias lub cev muaj pes tsawg leeg ntawm tib qhov xwm txheej muaj qhov sib txawv thaum txoj kev xav tom qab stoichiometry yog tias tag nrho cov huab hwm coj ntawm cov reactants sib npaug tag nrho cov khoom.
Summary – Dimensional Analysis vs Stoichiometry
Qhov sib txawv tseem ceeb ntawm qhov ntsuas qhov ntev thiab stoichiometry yog qhov ntsuas qhov loj me yog qhov hloov pauv ntawm tus nqi hauv ib chav mus rau tus nqi sib xws hauv chav xav tau siv ntau yam kev hloov pauv thaum stoichiometry koom nrog kev sib raug zoo ntawm cov reactants thiab / lossis cov khoom hauv Cov tshuaj tiv thaiv tshuaj los txiav txim seb cov ntaub ntawv xav tau ntau npaum li cas.
