Te Whakamahi i ngā Pūmau Taurite i roto i ngā Tātaitanga
Pendahuluan
Ko te taurite matū he ariā taketake i roto i te matū e whakaahua ana i te āhua e puta ai ngā tauhohenga whakamua me ngā tauhohenga whakamuri i te tere kotahi, kia mau tonu ai te kukū o ngā matū tauhohenga me ngā hua i roto i te wā. Ko tētahi o ngā huarahi matua ki te mārama ki te taurite ko te whakamahi i te pūmau taurite (K).
Ka tūhuratia hohonutia e tēnei tuhinga te whakamahinga o te pūmau taurite i roto i ngā tātaitanga. Ka hipokina e mātou te huarahi ki te tātai i te K, me pēhea te whakamahi i tēnei ki ngā tātaitanga kukū taurite, me pēhea hoki te pānga o ngā āhuatanga o waho ki te taurite.
Te Mārama ki te Pūmau Taurite
Ko te pūmau taurite, K, he tau e tohu ana i te tūnga taurite o tētahi tauhohenga matū. Ko te ōwehenga tēnei o ngā kukū o ngā hua ki ngā kukū o ngā matū tauhohe, ia mea kua whakapikihia ki te mana e rite ana ki tōna tauwehenga stoichiometric i roto i te whārite matū.
Hei tauira, mō te tauhohenga:
\[aA + bB \rightleftharpoons cC + dD\]
Ko te pūmau taurite ko:
\[K = \frac{[C]^c [D]^d}{[A]^a [B]^b}\]
I konei, ko \([A]\), \([B]\), \([C]\), me \([D]\) ngā kukū taurite o ngā matū tauhohenga me ngā hua, ko \(a\), \(b\), \(c\), me \(d\) ia ngā taunga o ia matū i roto i te tauhohenga.
Te Tātai i te Pūmau Taurite
Hei tatau i te K, me whai i ngā kukū o ngā matū i te taurite. Hei tauira, mō te tauhohenga whakapae o mua, ki te mōhio tātou ki ngā kukū o A, B, C, me D i te taurite, ka taea e tātou te whakakapi noa i ēnei uara ki te whārite mō te K.
Tauira:
Me kī koinei te tauhohenga e whai ake nei i tētahi pāmahana:
\[2SO_2(g) + O_2(g) \harpoons mataumaumau 2SO_3(g)\]
Mena kei roto i te taurite, kei a tātou:
\[[SO_2] = 0.2 \, \text{M}\]
\[[O_2] = 0.1 \, \text{M}\]
\[[SO_3] = 0.4 \, \text{M}\]
Ka tatauhia te pūmau taurite penei:
\[K = \frac{[SO_3]^2}{[SO_2]^2 [O_2]} = \frac{(0.4)^2}{(0.2)^2 (0.1)} = \frac{0.16}{0.004} = 40\]
Te Whakamahi i a K hei Matapae i te Kukū
Kia mōhiotia te uara K, ka taea e tātou te whakamahi hei whakatau i te kukū o tētahi matū i roto i tētahi pūnaha taurite.
Tauira:
Whakaarohia te tauhohenga:
\[H_2(g) + I_2(g) \rightleftharpoons 2HI(g)\]
Me te \(K = 50\) me te tauhohenga e tīmata ana me te kukū tīmatanga:
\[[H_2] = 1.0 \, \text{M}\]
\[[I_2] = 1.0 \, \text{M}\]
\[[HI] = 0 \, \text{M}\]
Me whakatau tātou i ngā kukū o ngā matū i te taurite.
Tuatahi, tautuhia te huringa o te kukū ina tae ki te taurite. Me waiho ko \(x\) te molarity o H_2 me I_2 e tauhohe ana, kātahi:
I te taurite:
\[[H_2] = 1.0 – x\]
\[[I_2] = 1.0 – x\]
\[[HI] = 2x\]
Whakamahia a K hei hanga i te whārite taurite:
\[K = \frac{[HI]^2}{[H_2][I_2]} = 50\]
\[\frac{(2x)^2}{(1.0 – x)(1.0 – x)} = 50\]
\[ \frac{4x^2}{(1.0 – x)^2} = 50\]
\[4x^2 = 50(1.0 – x)^2\]
\[4x^2 = 50(1.0 – 2x + x^2)\]
\[4x^2 = 50 – 100x + 50x^2\]
Whakaritea kia puta he whārite tapawhā:
\[50x^2 – 4x^2 – 100x + 50 = 0\]
\[46x^2 – 100x + 50 = 0\]
Whakamahia te tātai tapawhā hei whakaoti mō \(x\):
\[x = \frac{-b \pm \sqrt{b^2 – 4ac}}{2a}\]
Me \(a = 46\), \(b = -100\), me \(c = 50\):
\[x = \frac{100 \pm \sqrt{10000 – 9200}}{92}\]
\[x = \frac{100 \pm \sqrt{800}}{92}\]
\[x = \frac{100 \pm 28.28}{92}\]
\[x = \frac{128.28}{92} \text{ or } x = \frac{71.72}{92}\]
\[x = 1.395 \text{ or } x = 0.779\]
Ko te otinga anake \(x = 0.779\) te mea tika nā te mea kāore e taea e te kukū te neke ake i te kukū tīmatanga.
Nō reira ka noho te kukū taurite:
\[[H_2] = 1.0 – 0.779 = 0.221 \, \text{M}\]
\[[I_2] = 1.0 – 0.779 = 0.221 \, \text{M}\]
\[[HI] = 2(0.779) = 1.558 \, \text{M}\]
Te Awe o ngā Take Taiao o te Rohe
Ka pāngia te taurite e ngā āhuatanga pēnei i te pāmahana, te pēhanga, me te kukū. Mā te mātāpono a Le Chatelier ka āwhina i te matapae me pēhea te urupare a te pūnaha i te taurite ki ngā huringa o waho:
1. Huringa o te Kukū: Mā te tāpiri, te tango rānei i tētahi o ngā matū tauhohe, i ngā hua rānei, ka neke te pūnaha ki te whakahoki i te taurite e ai ki a K.
2. Ngā Huringa Pēhanga: Ka ngana ngā pūnaha hau ki te whakaiti, ki te whakanui rānei i te pēhanga mā te whakarerekē i te maha o ngā ngota hau.
3. Huringa Pāmahana: Ka huri te K mēnā ka huri te pāmahana. Mō ngā tauhohenga werawera (te mimiti i te wera), ka piki ake te K i te pikinga o te pāmahana, engari mō ngā tauhohenga werawera (te tuku wera), ka heke te K i te pikinga o te pāmahana.
Whakamutunga
He taputapu nui te pūmau taurite hei tātari me te matapae i te whanonga o ngā tauhohenga matū i te taurite. Mā te mārama pai ki te K, ka taea e tātou te tatau i te tūranga taurite me te mārama ki te awe o ngā āhuatanga o waho ki ngā tauhohenga taurite. Mā te whakamahi i ēnei mātāpono ka taea e tātou te whakahaere i ngā tauhohenga matū i roto i ngā horopaki ahumahi me te taiwhanga.
