Ukusebenzisa ama-Equilibrium Constants ekubaleni
I-Pendahuluan
Ukulingana kwamakhemikhali kuwumqondo oyisisekelo kumakhemikhali ochaza isimo lapho ukusabela okuya phambili nokuya emuva kwenzeka khona ngesivinini esifanayo, ukuze amazinga ezinto ezisabelayo kanye nemikhiqizo ahlale engaguquki ngokuhamba kwesikhathi. Enye yezindlela eziyinhloko zokuqonda ukulingana ukusebenzisa i-equilibrium constant (K).
Lesi sihloko sizohlola ukusetshenziswa kwe-equilibrium constant ekubaleni ngokujulile. Sizoxoxa ngendlela yokubala i-K, indlela yokuyisebenzisa ekubaleni kwe-equilibrium concentration, kanye nendlela izici zangaphandle ezingathinta ngayo i-equilibrium.
Ukuqonda Ukulingana Okuqhubekayo
I-equilibrium constant, K, iyinombolo ekhombisa indawo yokulingana yokusabela kwamakhemikhali. Yisilinganiso sokuhlushwa kwemikhiqizo nokugxila kwama-reactants, ngalinye liphakanyiswe emandleni ahambisana ne-stoichiometric coefficient yalo ku-chemical equation.
Isibonelo, mayelana nokusabela:
\[aA + bB \rightleftharpoons cC + dD\]
I-equilibrium constant yile:
\[K = \frac{[C]^c [D]^d}{[A]^a [B]^b}\]
Lapha, \([A]\), \([B]\), \([C]\), kanye \([D]\) yizinga lokulingana lama-reactants kanye nemikhiqizo, kuyilapho \(a\), \(b\), \(c\), kanye \(d\) kuyizinga lama-coefficients ento ngayinye ekuphenduleni.
Ukubala i-Equilibrium Constant
Ukuze sibale u-K, sidinga ukugxila kwezinto eziku-equilibrium. Isibonelo, ekusabeleni kwangaphambilini okucatshangelwayo, uma sazi ukugxila kuka-A, B, C, no-D ekulinganisweni, singamane sishintshe lawa manani sibe yi-equation ka-K.
Isibonelo:
Ake sithi sisabela ngokulandelayo ekushiseni okuthile:
\[2SO_2(g) + O_2(g) \rightleftharpoons 2SO_3(g)\]
Uma silingana kahle sinalokhu:
\[[SO_2] = 0.2 \, \umbhalo{M}\]
\[[O_2] = 0.1 \, \umbhalo{M}\]
\[[SO_3] = 0.4 \, \umbhalo{M}\]
I-equilibrium constant izobalwa kanje:
\[K = \frac{[SO_3]^2}{[SO_2]^2 [O_2]} = \frac{(0.4)^2}{(0.2)^2 (0.1)} = \frac{0.16}{0.004} = 40\]
Ukusebenzisa i-K ukubikezela ukugxila
Uma inani lika-K seliyaziwa, singalisebenzisa ukunquma ukuhlushwa kwento ohlelweni lokulingana.
Isibonelo:
Cabanga ngendlela abasabela ngayo:
\[H_2(g) + I_2(g) \rightleftharpoons 2HI(g)\]
Nge-\(K = 50\) kanye nokusabela okuqala ngokuhlushwa kokuqala:
\[[H_2] = 1.0 \, \umbhalo{M}\]
\[[I_2] = 1.0 \, \umbhalo{M}\]
\[[HI] = 0 \, \umbhalo{M}\]
Ake sithole ukuthi izinto zingakanani ngesikhathi sokulingana.
Okokuqala, chaza ushintsho ekugxileni lapho kufinyelelwa ukulingana. Ake kube yi-molarity ye-H_2 kanye ne-I_2 esabelayo, bese:
Ngesikhathi sokulingana:
\[[H_2] = 1.0 – x\]
\[[I_2] = 1.0 – x\]
\[[HI] = 2x\]
Sebenzisa u-K ukwakha i-equation yokulingana:
\[K = \frac{[HI]^2}{[H_2][I_2]} = 50\]
\[\frac{(2x)^2}{(1.0 – x)(1.0 – x)} = 50\]
\[ \frac{4x^2}{(1.0 – x)^2} = 50\]
\[4x^2 = 50(1.0 – x)^2\]
\[4x^2 = 50(1.0 – 2x + x^2)\]
\[4x^2 = 50 – 100x + 50x^2\]
Hlela kabusha ukuze wakhe i-quadratic equation:
\[50x^2 – 4x^2 – 100x + 50 = 0\]
\[46x^2 – 100x + 50 = 0\]
Sebenzisa ifomula ye-quadratic ukuxazulula i-\(x\):
\[x = \frac{-b \pm \sqrt{b^2 – 4ac}}{2a}\]
Nge-\(a = 46\), \(b = -100\), kanye ne-\(c = 50\):
\[x = \frac{100 \pm \sqrt{10000 – 9200}}{92}\]
\[x = \frac{100 \pm \sqrt{800}}{92}\]
\[x = \frac{100 \pm 28.28}{92}\]
\[x = \frac{128.28}{92} \text{ or } x = \frac{71.72}{92}\]
\[x = 1.395 \umbhalo{ noma } x = 0.779\]
Isixazululo \(x = 0.779\) kuphela esisebenzayo ngoba ukuhlushwa akukwazi ukudlula ukuhlushwa kokuqala.
Ngakho-ke ukuhlushwa kwe-equilibrium kuba:
\[[H_2] = 1.0 – 0.779 = 0.221 \, \umbhalo{M}\]
\[[I_2] = 1.0 – 0.779 = 0.221 \, \umbhalo{M}\]
\[[HI] = 2(0.779) = 1.558 \, \umbhalo{M}\]
Ithonya Lezinto Ezithinta Indawo Yemvelo
Izinto ezifana nokushisa, ingcindezi, kanye nokuhlushwa kungathinta ukulingana. Isimiso sikaLe Chatelier sisiza ukubikezela ukuthi uhlelo olusekulinganisweni luzosabela kanjani ezinguqukweni zangaphandle:
1. Ushintsho Ekugxileni: Ukwengeza noma ukususa enye ye-reactants noma imikhiqizo kuzokwenza uhlelo luhambe ukuze lubuyisele ukulingana ngokusho kwe-K.
2. Izinguquko Ekucindezelweni: Izinhlelo ezinegesi zizozama ukunciphisa noma ukwandisa ingcindezi ngokushintsha inani lama-molecule egesi.
3. Ukushintsha Kwezinga Lokushisa: U-K uzoshintsha uma izinga lokushisa lishintshwa. Ngokusabela kwe-endothermic (ukumunca ukushisa), ukwanda kwezinga lokushisa kuzokwandisa u-K, kanti ngokusabela kwe-exothermic (ukukhulula ukushisa), ukwanda kwezinga lokushisa kuzonciphisa u-K.
Isiphetho
I-equilibrium constant iyithuluzi elibalulekile ekuhlaziyeni nasekubikezeleni ukuziphatha kwe-chemical reactions ku-equilibrium. Ngokuqonda kahle i-K, singabala isikhundla se-equilibrium futhi siqonde ithonya lezinto zangaphandle ekuphenduleni kwe-equilibrium. Ukusebenzisa lezi zimiso kusenza sikwazi ukulawula i-chemical reactions ezimweni ezahlukahlukene zezimboni neze-laboratory.
