Piv txwv cov lus nug thiab kev sib tham txog qhov sib npaug ntawm cov khoom siv
Pendahuluuan
Tsab xov xwm no yuav tham txog thiab muab cov piv txwv ntawm cov teeb meem ntsig txog qhov sib npaug tas li, ib lub tswv yim tseem ceeb hauv chemistry. Qhov sib npaug tas li (K) yog ib qho parameter uas piav qhia txog qhov sib npaug ntawm cov tshuaj tiv thaiv hauv qee qhov xwm txheej. K yog siv los nkag siab tias qhov tshuaj tiv thaiv mus deb npaum li cas ua ntej mus txog qhov sib npaug. Thaum qhov tshuaj tiv thaiv mus txog qhov sib npaug, cov nqi ntawm cov tshuaj tiv thaiv pem hauv ntej thiab rov qab yog sib npaug, yog li qhov concentration ntawm cov reactants thiab cov khoom tseem nyob ruaj khov. Tsab xov xwm no yuav suav nrog cov lus txhais, cov mis, thiab cov teeb meem piv txwv uas muaj txiaj ntsig zoo rau kev nkag siab tob txog qhov sib npaug tas li.
Kev Txhais Lus ntawm Equilibrium Constant
Tus nqi sib npaug tas li yog tus nqi uas qhia txog qhov sib piv ntawm qhov concentration ntawm cov khoom rau qhov concentration ntawm cov reactants ntawm qhov sib npaug. Cov qauv dav dav rau qhov sib npaug tas li yog raws li nram no:
\[ K_c = \frac{[\text{Khoom}]^\text{coefficient}}{[\text{Reagent}]^\text{coefficient}} \]
qhov twg \(K_c\) yog qhov sib npaug tas li hauv qhov concentration (mol/L), thaum cov khoom thiab cov reactants yog qhov concentration ntawm cov tshuaj uas koom nrog hauv qhov kev tshuaj tiv thaiv ntawm qhov sib npaug.
Cov mis sib npaug tas li
Rau cov kev tshuag dav dav:
\[ aA + bB \leftrightarrow cC + dD \]
Cov mis rau qhov sib npaug tas li yog:
\[ K_c = \frac{[C]^c[D]^d}{[A]^a[B]^b} \]
Cov Lus Nug Piv Txwv thiab Kev Sib Tham
Piv txwv lus nug 1:
Cov tshuaj tiv thaiv hauv qab no yog nyob rau hauv qhov sib npaug ntawm qee qhov kub thiab txias:
\[ 2NO_2 (g) \leftrightarrow N_2O_4 (g) \]
Paub tias thaum muaj qhov sib npaug, qhov concentration ntawm \(NO_2\) yog 0,5 M thiab qhov concentration ntawm \(N_2O_4\) yog 0,2 M. Txheeb xyuas qhov sib npaug tas mus li, \(K_c\), rau qhov kev tshuaj tiv thaiv no.
Kev Sib Tham:
Raws li cov tshuaj tiv thaiv tau muab:
\[ 2NO_2 (g) \leftrightarrow N_2O_4 (g) \]
Tus qauv sib npaug tas li rau qhov kev tshuaj tiv thaiv no yog:
\[ K_c = \frac{[N_2O_4]}{[NO_2]^2} \]
Sau cov nqi uas paub lawm:
\[ K_c = \frac{0,2}{(0,5)^2} = \frac{0,2}{0,25} = 0,8 \]
Yog li, qhov sib npaug tas mus li yog \(K_c = 0,8\).
Piv txwv lus nug 2:
Hauv cov tshuaj tiv thaiv hauv qab no:
\[ H_2 (g) + I_2 (g) \leftrightarrow 2HI (g) \]
Yog tias nyob rau ntawm qhov sib npaug, qhov concentration ntawm \(H_2\) yog 0,1 M, qhov concentration ntawm \(I_2\) yog 0,1 M thiab qhov concentration ntawm \(HI\) yog 0,4 M, xam qhov sib npaug tas mus li, \(K_c\), rau qhov kev tshuaj tiv thaiv no.
Kev Sib Tham:
Raws li cov tshuaj tiv thaiv tau muab:
\[ H_2 (g) + I_2 (g) \leftrightarrow 2HI (g) \]
Tus qauv sib npaug tas li rau qhov kev tshuaj tiv thaiv no yog:
\[ K_c = \frac{[HI]^2}{[H_2][I_2]} \]
Sau cov nqi uas paub lawm:
\[ K_c = \frac{(0,4)^2}{(0,1)(0,1)} = \frac{0,16}{0,01} = 16 \]
Yog li, qhov sib npaug tas mus li yog \(K_c = 16\).
Piv txwv lus nug 3:
Cov tshuaj tiv thaiv hauv qab no yog nyob rau hauv qhov sib npaug ntawm qee qhov kub thiab txias:
\[ 2SO_2 (g) + O_2 (g) \leftrightarrow 2SO_3 (g) \]
Yog tias nyob rau ntawm qhov sib npaug, qhov concentration ntawm \(SO_2\) yog 0,3 M, qhov concentration ntawm \(O_2\) yog 0,2 M thiab qhov concentration ntawm \(SO_3\) yog 0,5 M, xam qhov sib npaug tas mus li, \(K_c\), rau qhov kev tshuaj tiv thaiv no.
Kev Sib Tham:
Raws li cov tshuaj tiv thaiv tau muab:
\[ 2SO_2 (g) + O_2 (g) \leftrightarrow 2SO_3 (g) \]
Tus qauv sib npaug tas li rau qhov kev tshuaj tiv thaiv no yog:
\[ K_c = \frac{[SO_3]^2}{[SO_2]^2[O_2]} \]
Sau cov nqi uas paub lawm:
\[ K_c = \frac{(0,5)^2}{(0,3)^2(0,2)} = \frac{0,25}{0,09 \times 0,2} = \frac{0,25}{0,018} = 13.89 \]
Yog li, qhov sib npaug tas mus li yog \(K_c = 13,89\).
Piv txwv lus nug 4:
Hauv cov tshuaj tiv thaiv hauv qab no:
\[ N_2 (g) + 3H_2 (g) \leftrightarrow 2NH_3 (g) \]
Yog tias, qhov sib txawv, qhov concentration ntawm \(N_2\) yog 0,3 M, qhov concentration ntawm \(H_2\) yog 0,4 M thiab qhov concentration ntawm \(NH_3\) yog 1,2 M, xam qhov sib npaug tas mus li, \(K_c\), rau qhov kev tshuaj tiv thaiv no.
Kev Sib Tham:
Raws li cov tshuaj tiv thaiv tau muab:
\[ N_2 (g) + 3H_2 (g) \leftrightarrow 2NH_3 (g) \]
Tus qauv sib npaug tas li rau qhov kev tshuaj tiv thaiv no yog:
\[ K_c = \frac{[NH_3]^2}{[N_2][H_2]^3} \]
Sau cov nqi uas paub lawm:
\[ K_c = \frac{(1,2)^2}{(0,3)(0,4)^3} = \frac{1,44}{(0,3)(0,064)} = \frac{1,44}{0,0192} = 75 \]
Yog li, qhov sib npaug tas mus li yog \(K_c = 75\).
Kev kaw
Qhov sib npaug tas li yog lub tswv yim tseem ceeb hauv chemistry uas pab peb nkag siab tias cov tshuaj tiv thaiv mus txog qhov sib npaug li cas thiab qhov concentration ntawm cov reactants thiab cov khoom cuam tshuam li cas rau qhov sib npaug. Los ntawm kev nkag siab cov piv txwv thiab kev sib tham saum toj no, nws vam tias cov nyeem ntawv yuav muaj daim duab meej dua thiab muaj peev xwm daws cov teeb meem txog qhov sib npaug tas li nrog kev ntseeg siab ntau dua.
Kev paub txog qhov sib npaug ntawm qhov tsis hloov pauv tsis yog tsuas yog muaj txiaj ntsig zoo rau kev xav xwb tab sis kuj tseem siv tau rau hauv ntau qhov chaw xws li kev lag luam tshuaj lom neeg, tshuaj, thiab kev tshawb fawb. Yog li ntawd, kev nkag siab zoo txog lub tswv yim no yog qhov tseem ceeb rau txhua tus neeg uas kawm lossis ua haujlwm nrog cov tshuaj lom neeg.
