Cov Lus Nug Piv Txwv Sib Tham Txog Kev Sib Npaug Tshuaj Hauv Ntiaj Teb Kev Lag Luam
Kev sib npaug ntawm cov tshuaj lom neeg yog lub tswv yim tseem ceeb hauv chemistry thiab siv tau dav hauv ntau qhov chaw lag luam. Hauv kev tshuaj lom neeg, kev sib npaug tshwm sim thaum tus nqi ntawm kev tshuaj tiv thaiv pem hauv ntej sib npaug rau tus nqi ntawm kev tshuaj tiv thaiv rov qab, yog li qhov kev sib xyaw ntawm cov tshuaj reactants thiab cov khoom lag luam tseem nyob ruaj khov dhau sijhawm. Ntau lub lag luam, xws li tshuaj, petrochemicals, thiab kev ua zaub mov, vam khom kev nkag siab thiab tswj kev sib npaug ntawm cov tshuaj lom neeg kom ua kom zoo dua qub thiab ua haujlwm tau zoo. Tsab xov xwm no yuav tham txog ntau qhov piv txwv ntawm cov teeb meem cuam tshuam nrog kev sib npaug ntawm cov tshuaj lom neeg hauv kev lag luam thiab yuav daws lawv li cas.
Piv txwv lus nug 1: Kev lag luam ammonia (Haber-Bosch Txheej Txheem)
Lo lus nug:
Cov txheej txheem Haber-Bosch tsim cov ammonia (NH3)3) los ntawm nitrogen (N2) thiab hydrogen (H2) raws li qhov kev tshuaj tiv thaiv:
\[ \text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g) \]
Ntawm 500 K, qhov sib npaug tas mus li (Kc ) rau qhov kev tshuaj tiv thaiv no yog 6.0 x 10^-2. Yog tias peb pib nrog 1.00 mol N2 thiab 3.00 mol H2 hauv lub reactor nrog qhov ntim ntawm 1.00 L, xam qhov concentration ntawm txhua yam khoom ntawm qhov sib npaug.
Kev Sib Tham:
1. Txheeb xyuas qhov kev hloov pauv ntawm qhov concentration rau txhua feem hauv lub system.
\[ \text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g) \]
Cia x yog cov moles ntawm NH3 uas yog tsim ntawm qhov sib npaug, ces qhov kev hloov pauv ntawm qhov concentration yog raws li nram no:
- Tsis muaj2: -x mol/L
- H2: -3x mol/L
– NH3: +2x mol/L
2. Npaj qhov sib npaug ntawm qhov sib npaug raws li qhov sib npaug tas li (Kc):
\[
K_c = \frac{[\text{NH}_3]^2}{[\text{N}_2][\text{H}_2]^3} = 6.0 \times 10^{-2}
\]
Kev tsom xam thawj zaug thiab kev hloov pauv ntawm kev tsom xam:
– [N]2] = 1.00 – x
– [H2] = 3.00 – 3x
– [NH]3] = 2x
3. Muab cov nqi no ntsaws rau hauv qhov sib npaug ntawm qhov sib npaug:
\[
6.0 \times 10^{-2} = \frac{(2x)^2}{(1.00 – x)(3.00 – 3x)^3}
\]
4. Xam tus nqi ntawm x siv kev sim thiab qhov yuam kev lossis lwm txoj kev suav lej los daws qhov sib npaug.
Tom qab kev xam, peb tau txais x = 0.46. Yog li:
– [N]2= 1.00 – 0.46 = 0.54 mol/L
– [H2= 3.00 – 3 (0.46) = 1.62 mol/L
– [NH]3] = 2(0.46) = 0.92 mol/L
Piv txwv lus nug 2: Kev lag luam sulfuric acid (Txheej txheem sib cuag)
Lo lus nug:
Hauv cov txheej txheem sib cuag, kev hloov pauv ntawm sulfur dioxide (SO4)2) rau hauv sulfur trioxide (SO4)3) los ntawm qhov kev tshuaj tiv thaiv:
\[ 2\text{SO}_2(g) + \text{O}_2(g) \rightleftharpoons 2\text{SO}_3(g) \]
Qhov sib npaug tas li (Kc ) rau qhov kev tshuaj tiv thaiv no ntawm 600 K yog 350. Yog tias lub reactor muaj 0.50 mol SO2 , 0.25 mol O2 , thiab 0.10 mol SO3 , xam cov concentration ntawm cov khoom ntawm qhov sib npaug hauv qhov ntim ntawm 2.00 L.
Kev Sib Tham:
1. Txheeb xyuas qhov concentration pib:
– [SO]2]pib = 0.50 mol / 2.00 L = 0.25 M
– [O]2]pib = 0.25 mol / 2.00 L = 0.125 M
– [SO]3]pib = 0.10 mol / 2.00 L = 0.05 M
2. Cia x yog qhov kev hloov pauv ntawm SO concentration.3 uas yog tsim los ntawm qhov sib npaug:
– [SO]2]: 0.25 – x
– [O]2]: 0.125 – \(\frac{x}{2}\)
– [SO]3]: 0.05 + x
3. Txuas rau hauv qhov sib npaug ntawm qhov sib npaug:
\[
350 = \frac{(0.05 + x)^2}{(0.25 – x)^2 \cdot (0.125 – x}{2})}
\]
4. Los ntawm kev daws qhov sib npaug no (siv txoj kev suav lej lossis siv lub tshuab xam zauv programmable), nws pom tias x = 0.165. Ces:
– [SO]2] = 0.25 – 0.165 = 0.085 M
– [O]2] = 0.125 – \(\frac{0.165}{2}\) = 0.0425 M
– [SO]3] = 0.05 + 0.165 = 0.215 M
Piv txwv lus nug 3: Kev tsim cov Ethylbenzene
Lo lus nug:
Hauv kev tsim cov ethylbenzene, styrene yog tsim los ntawm dehydrogenation ntawm ethylbenzene (C6H5CH2CH3):
\[ \text{C}_6\text{H}_5\text{CH}_2\text{CH}_3(g) \rightleftharpoons \text{C}_6\text{H}_5\text{CH=CH}_2(g) + \text{H}_2(g) \]
Yog tias qhov sib npaug tas li (Kc ) rau qhov tshuaj tiv thaiv no ntawm 700 K yog 2.5, thiab thaum xub thawj muaj 1.0 mol ntawm ethylbenzene hauv qhov ntim ntawm 1.0 L, xam qhov concentration ntawm qhov sib npaug.
Kev Sib Tham:
1. Txheeb xyuas qhov concentration pib:
– [C6H5CH2CH3] = 1.0 M
– [C6H5CH=CH2] = 0 M (vim nws tsis tau raug rhuav tshem)
– [H2] = 0 M
2. Cia x yog qhov kev hloov pauv ntawm qhov concentration ntawm C6H5CH=CH2 uas yog tsim los ntawm qhov sib npaug:
– [C6H5CH2CH3]: 1.0 – x
– [C6H5CH=CH2]: x
– [H2]: x
3. Txuas rau hauv qhov sib npaug ntawm qhov sib npaug:
\[
2.5 = x = x = 1.0 – x = 2.0 – x
\]
4. Los ntawm kev daws qhov kev sib npaug quadratic no, nws pom tias x = 0.62. Ces:
– [C6H5CH2CH3] = 1.0 – 0.62 = 0.38 M
– [C6H5CH=CH2] = 0.62 M
– [H2] = 0.62 M
Hauv peb qhov piv txwv no, peb tau pom tias lub tswv yim ntawm kev sib npaug ntawm cov tshuaj lom neeg siv li cas hauv ntau yam kev lag luam. Kev sib npaug ntawm cov tshuaj lom neeg yog lub hauv paus tseem ceeb thiab tseem ceeb hauv cov txheej txheem kev lag luam, vim tias kev tswj hwm qhov sib npaug ntawm cov tshuaj lom neeg tuaj yeem txhim kho kev ua haujlwm zoo thiab cov khoom zoo. Kev nkag siab zoo txog kev sib npaug ntawm cov tshuaj lom neeg ua rau tus kws ua haujlwm lossis tus kws kho mob hauv kev lag luam tsim thiab ua haujlwm cov txheej txheem zoo tshaj plaws.
