Mibvunzo yeMienzaniso neKukurukurirana kweArrhenius Acids neBases
Asidhi nemabhesi ipfungwa huru mukemistri. Imwe yedzidziso dzinozivikanwa zvikuru dzekutsanangura maitiro emaacid nemabhesi idzidziso yeArrhenius. Sekureva kwaArrhenius, asidhi chinhu chinoumbwa mumvura, chinoburitsa H⁺ (kana H₃O⁺) ions, nepo hwaro chiri chinhu chinoumbwa mumvura, chinoburitsa OH⁻ ions. Muchinyorwa chino, tichakurukura mienzaniso yakati wandei yezvinetso zvine chekuita nemaacid nemabhesi zvichienderana nedzidziso yeArrhenius, pamwe chete nemhinduro dzacho.
Muenzaniso Mubvunzo 1
Mubvunzo:
Mhinduro ye 0,1 M hydrochloric acid (HCl) inonyungudutswa mumvura. Verenga huwandu hweH⁺ ions mumushonga.
Kukurukurirana:
Zvinoenderana nedzidziso yeArrhenius, HCl iasidhi nekuti inogadzira H⁺ ions kana yanyungudutswa mumvura. Equation yeionization yeHCl mumvura ndeiyi inotevera:
\[ \text{HCl} \kuna \text{H}^+ + \text{Cl}^- \]
Kuwanda kwekutanga kweHCl kuri 0,1 M. Sezvo HCl iri acid yakasimba inoisa ioni mu aqueous solution, HCl molecule yega yega ichagadzira H⁺ ion imwe chete uye Cl⁻ ion imwe chete. Saka, kuwanda kwema H⁺ ions mumushonga kwakaenzanawo nekuwanda kweHCl, kureva:
\[ [\text{H}^+] = 0,1 \text{M} \]
Saka, huwandu hweH⁺ ions mu 0,1 M HCl solution i0,1 M.
Muenzaniso Mubvunzo 2
Mubvunzo:
Verenga pH ye 0,01 M nitric acid (HNO₃) solution.
Kukurukurirana:
HNO₃ iasidhi yakasimba inoisa ioni mumvura yese, saka equation ye ionization yeHNO₃ ndeiyi inotevera:
\[ \text{HNO}_3 \kuna \text{H}^+ + \text{HAKUNA}_3^- \]
Kuwanda kweHNO₃ kwakapihwa i0,01 M. Sezvo HNO₃ iri acid yakasimba, molekyuru yega yega yeHNO₃ ichagadzira H⁺ ion imwe chete. Saka, kuwanda kwemaH⁺ ions mumushonga kwakaenzana nekuwanda kweHNO₃, kureva:
\[ [\text{H}^+] = 0,01 \text{M} \]
pH inogona kuverengerwa uchishandisa fomura:
\[ \text{pH} = -\log [\text{H}^+] \]
Nekubatanidza huwandu hweH⁺ ions mufomura, tinowana:
\[ \text{pH} = -\log (0,01) = -\log (10^{-2}) = 2 \]
Saka, pH ye 0,01 M HNO₃ solution i2.
Muenzaniso Mubvunzo 3
Mubvunzo:
Tsvaga huwandu hweOH⁻ ions mu 0,05 M NaOH solution.
Kukurukurirana:
NaOH ihwaro hwakasimba hunoisa ionizes zvizere mumvura, saka equation yeionization yeNaOH ndeiyi inotevera:
\[ \chinyorwa{NaOH} \ku\chinyorwa{Na}^+ + \zvinyorwa{OH}^- \]
Kuwanda kweNaOH kwakapihwa i0,05 M. Sezvo NaOH iri hwaro hwakasimba, molekyuru yega yega yeNaOH ichagadzira OH⁻ ion imwe chete. Nokudaro, kuwanda kwemaion eOH⁻ mumushonga kwakaenzana nekuwanda kweNaOH, kureva:
\[ [\text{OH}^-] = 0,05 \text{M} \]
Saka, huwandu hweOH⁻ ions mu 0,05 M NaOH solution i0,05 M.
Muenzaniso Mubvunzo 4
Mubvunzo:
Verenga pH ye 0,01 M KOH solution.
Kukurukurirana:
KOH ihwaro hwakasimba hunoonekwa mumvura. Equation ye ionization yeKOH mumvura ndeiyi inotevera:
\[ \text{KOH} \kuna \text{K}^+ + \text{OH}^- \]
Kuwanda kweKOH kwakapihwa i0,01 M. Sezvo KOH iri hwaro hwakasimba, molekyuru yega yega yeKOH ichagadzira OH⁻ ion imwe chete. Nokudaro, kuwanda kwema OH⁻ ions mumushonga kwakaenzana nekuwanda kweKOH, kureva:
\[ [\text{OH}^-] = 0,01 \text{M} \]
pH chiyero chekuwanda kwemaion eH⁺ mumushonga. Tinogona kushandisa hukama huripo pakati pemaion epH, H⁺, uye OH⁻ anopiwa nechigadzirwa cheion yemvura (Kw):
\[ \text{Kw} = [\text{H}^+][\text{OH}^-] = 1 \times 10^{-14} \]
Tichiziva kukosha kwe [OH⁻], tinogona kuverenga [H⁺]:
\[ [\text{H}^+] = \frac{\text{Kw}}{[\text{OH}^-]} = \frac{1 \times 10^{-14}}{0,01} = 1 \times 10^{-12} \text{M} \]
pH inogona kuverengerwa uchishandisa fomura:
\[ \text{pH} = -\log [\text{H}^+] \]
Nekubatanidza huwandu hweH⁺ ions mufomura, tinowana:
\[ \text{pH} = -\log (1 \kawa 10^{-12}) = 12 \]
Saka, pH ye 0,01 M KOH solution i12.
Muenzaniso Mubvunzo 5
Mubvunzo:
Mhinduro ine pH = 3. Verenga huwandu hweH⁺ ions mumushonga.
Kukurukurirana:
pH chiyero chekuwanda kwemaion eH⁺ mumushonga uye chinogona kuratidzwa nefomura iyi:
\[ \text{pH} = -\log [\text{H}^+] \]
Kuti tiverenge huwandu hweH⁺ ions, tinochinja fomura kuita:
\[ [\text{H}^+] = 10^{-\text{pH}} \]
Nekubatanidza pH yakapihwa, tinowana:
\[ [\text{H}^+] = 10^{-3} = 0,001 \text{M} \]
Saka, huwandu hweH⁺ ions mumushonga une pH = 3 i0,001 M.
Muenzaniso Mubvunzo 6
Mubvunzo:
Mhinduro yeNH₄OH ine huwandu hwe0,1 M. Verenga pH yemhinduro kana kukosha kweKb kweNH₄OH kuri 1,8 x 10⁻⁵.
Kukurukurirana:
NH₄OH ihwaro husina kusimba husingaite ioni zvachose mumvura. Equation yeionization yeNH₄OH mumvura ndeiyi inotevera:
\[ \text{NH}_4\text{OH} \leftrightarrow \text{NH}_4^+ + \text{OH}^- \]
Iyo equilibrium constant ye ionization yeNH₄OH inonzi Kb uye inopiwa na:
\[ K_b = \frac{[\text{NH}_4^+][\text{OH}^-]}{[\text{NH}_4\text{OH}} \]
Sezvo NH₄OH iri base isina simba, tinoshandisa Kb kuverenga huwandu hweOH⁻ ions. Tichifunga kuti \(x\) ndiyo huwandu hweNH₄OH ine ionized, equation yeionization inova:
\[ K_b = \frac{x^2}{0,1 – x} \approx \frac{x^2}{0,1} \]
Sezvo kukosha kweKb kuri kudiki kwazvo, tinofungidzira \(0,1 – x \approx 0,1\):
\[ 1,8 \kawa 10^{-5} = \frac{x^2}{0,1} \]
\[ x^2 = 1,8 \kawa 10^{-6} \]
\[ x = \sqrt{1,8 \kawa 10^{-6}} \]
\[ x \inenge 1,34 \kawa 10^{-3} \mashoko{ M} \]
Saka, huwandu hweOH⁻ ions ndi \(1,34 \times 10^{-3} \text{ M}\).
Kubva pakuwanda uku, tinogona kuverenga kuwanda kwema H⁺ ions tichishandisa Kw:
\[ [\text{H}^+] = \frac{1 \times 10^{-14}}{1,34 \times 10^{-3}} \]
\[ [\text{H}^+] = 7,46 \kawa 10^{-12} \text{M} \]
pH:
\[ \text{pH} = -\log (7,46 \kawa 10^{-12}) \]
\[ \text{pH} \inenge 11,13 \]
Saka, pH ye 0,1 M NH₄OH solution inenge 11,13.
Mhedziso
Dzidziso yeArrhenius inopa hwaro hunokosha hwekunzwisisa mashandiro anoita maasidhi nemabhesi mumhinduro. Muhurukuro iyi, takatarisa mienzaniso yakati wandei yezvinetso zvinoratidza kuti pfungwa idzi dzinogona kushandiswa sei kuverenga huwandu hweH⁺ neOH⁻ ions uye pH yemhinduro dzakasiyana-siyana. Kunzwisisa dzidziso iyi kwakakosha kune chero munhu ari kutsvaga basa mukemistri, kungave kuchikoro chesekondari kana padanho redzidzo yepamusoro.
