Mohlala oa Lipotso tsa Puisano ea Titration ea Asiti-Base
Titration ea motheo oa asiti ke e 'ngoe ea mekhoa e tloaelehileng ea tlhahlobo ea bongata k'hemistri. Mokhoa ona o kenyelletsa karabelo pakeng tsa asiti le motheo ho fumana hore na tharollo e na le bokae. Sehloohong sena, re tla tšohla mehlala e 'maloa ea mathata a titration ea motheo oa asiti le litharollo tsa ona, re ikemiselitse ho u thusa ho utloisisa likhopolo tsa motheo le mokhoa oa ho li etsa.
Mehopolo ea Motheo ea Titration ea Asiti-Base
Li-titrations tsa motheo oa asiti li kenyelletsa karabelo ea ho se nke lehlakore pakeng tsa li-ion tsa hydrogen (H⁺) ho tsoa ho li-ion tsa asiti le hydroxide (OH⁻) ho tloha motheong ho etsa metsi (H₂O). Ntlha ea ho lekana ke ntlha eo palo ea li-moles tsa asiti e lekanang le palo ea li-moles tsa motheo tse ekelitsoeng. Nakong ena, karabelo pakeng tsa asiti le motheo e etsahetse ka botlalo.
Foromo e Akaretsang
Foromo ea motheo e sebelisoang ho titration ea acid-base ke:
\[ n_{a} \cdot M_{a} \cdot V_{a} = n_{b} \cdot M_{b} \cdot V_{b} \]
Moo:
– \( n_{a} \) ke valence ea asiti,
– \( M_{a} \) ke molarity ea asiti,
– \( V_{a} \) ke bophahamo ba asiti,
– \( n_{b} \) ke valence ea motheo,
– \( M_{b} \) ke molarity ea motheo,
– \( V_{b} \) ke bophahamo ba motheo.
Pampiri ea Litmus le Lipontšo
Mokgweng wa ho etsa titration, ditshupiso tsa motheo wa asiti tse kang phenolphthalein kapa methyl orange hangata di sebediswa ho fumana ntlha ya ho lekana. Ditshupiso tsena di fetola mmala ho pH e itseng, e leng se bontshang hore ntlha ya ho lekana e fihlelletswe.
Lipotso tsa Mehlala le Puisano
Mohlala oa Potso ea 1: Titration ea Asiti e Matla le Motheo o Matla
Potso:
Hoa tsebahala hore 25 mL ea tharollo ea 0,1 M HCl e na le titration ka tharollo ea 0,1 M NaOH. Ke bophahamo bofe ba NaOH bo hlokahalang ho fihlela ntlha ea ho lekana?
Puisano:
Karabelo pakeng tsa HCl le NaOH ke:
\[ HCl + NaOH \ motsu NaCl + H_2O \]
Mohato oa 1: Fumana li-moles tsa H⁺ ho tsoa ho HCl
\[ n_{\text{HCl}} = M_{\text{HCl}} \times V_{\text{HCl}} \]
\[ n_{\text{HCl}} = 0,1 \times 0,025 = 0,0025 \text{mol} \]
Mohato oa 2: Fumana bophahamo ba NaOH bo hlokahalang
Hobane HCl le NaOH li na le karolelano ea 1:1 karabelong (n = 1):
\[ n_{\text{HCl}} = n_{\text{NaOH}} \]
\[ M_{\text{NaOH}} \times V_{\text{NaOH}} = 0,0025 \text{mol} \]
\[ V_{\text{NaOH}} = \frac{0,0025 \text{ mol}}{0,1 \text{ M}} = 0,025 \text{ L} = 25 \text{ mL} \]
Kahoo, bophahamo ba NaOH bo hlokahalang ke 25 mL.
Mohlala oa Potso ea 2: Titration ea Asiti e Fokolang le Motheo o Matla
Potso:
Kakaretso ea 50 mL ea tharollo ea 0,1 M acetic acid (CH₃COOH) e ile ea kenngoa ka tharollo ea 0,1 M NaOH. Ke bophahamo bofe ba NaOH bo hlokahalang ho fihlela ntlha ea ho lekana?
Puisano:
Karabelo pakeng tsa asiti ea acetic le NaOH ke:
\[ CH_3COOH + NaOH \ motsu o ka ho le letona CH_3COONA + H_2O \]
Mohato oa 1: Fumana li-moles tsa H⁺ ho tsoa ho CH₃COOH
\[ n_{\text{CH}_3\text{COOH}} = M_{\text{CH}_3\text{COOH}} \times V_{\text{CH}_3\text{COOH}} \]
\[ n_{\text{CH}_3\text{COOH}} = 0,1 \times 0,05 = 0,005 \text{mol} \]
Mohato oa 2: Fumana bophahamo ba NaOH bo hlokahalang
Hobane karolelano ea mole pakeng tsa CH₃COOH le NaOH ke 1:1:
\[ n_{\text{CH}_3\text{COOH}} = n_{\text{NaOH}} \]
\[ M_{\text{NaOH}} \times V_{\text{NaOH}} = 0,005 \text{mol} \]
\[ V_{\text{NaOH}} = \frac{0,005 \text{ mol}}{0,1 \text{ M}} = 0,05 \text{ L} = 50 \text{ mL} \]
Kahoo, bophahamo ba NaOH bo hlokahalang ke 50 mL.
Mohlala oa Potso ea 3: Titration ea Polyprotic ea Li-Acid le Metheo e Matla
Potso:
Hoa tsebahala hore 40 mL ea tharollo ea 0,05 M H₂SO₄ e na le titration ka tharollo ea 0,1 M KOH. Ke bophahamo bofe ba KOH bo hlokahalang ho fihlela lintlha tsa pele le tsa bobeli tsa ho lekana?
Puisano:
H₂SO₄ ke diprotic acid e ka lokollang li-ion tse peli tsa H⁺. Karabelo le KOH e mekhahlelo e 'meli:
\[ H_2SO_4 + 2KOH \ motsu K_2SO_4 + 2H_2O \]
Mohato oa 1: Fumana li-moles tsa H⁺ ho tsoa ho H₂SO₄
\[ n_{\text{H}_2\text{SO}_4} = M_{\text{H}_2\text{SO}_4} \times V_{\text{H}_2\text{SO}_4} \]
\[ n_{\text{H}_2\text{SO}_4} = 0,05 \times 0,04 = 0,002 \text{mol} \]
Mohato oa 2: Fumana bophahamo ba KOH bo hlokahalang mohatong ka mong
Karolong ea pele ea titration (ho lokolla H⁺ e le 'ngoe):
\[ n_{\text{H}_2\text{SO}_4} = n_{\text{KOH}} \]
\[ M_{\text{KOH}} \times V_{\text{KOH}} = 0,002 \text{ mol} \]
\[ V_{\text{KOH}}_{\text{first}} = \frac{0,002 \text{ mol}}{0,1 \text{ M}} = 0,02 \text{ L} = 20 \text{ mL} \]
Ka titration ea bobeli (ho tlosa H⁺ tse peli) habeli li-moles tse fetileng lia hlokahala:
\[ n_{\text{KOH}}_{\text{second}} = 2 \times 0,002 \text{ mol} = 0.004 \text{ mol} \]
\[ V_{\text{KOH}}_{\text{second}} = \frac{0.004 \text{ mol}}{0,1 \text{ M}} = 0,04 \text{ L} = 40 \text{ mL} \]
Kahoo, bophahamo ba KOH bo hlokahalang bakeng sa ntlha ea pele ea ho lekana ke 20 mL, 'me bakeng sa ntlha ea bobeli ea ho lekana ke 40 mL.
Qetello
Ka mehlala e 'maloa ea titration ea acid-base e kaholimo, re ithutile mokhoa oa ho fumana bophahamo ba tharollo bo hlokahalang ho fihlela ntlha ea ho lekana mefuteng e fapaneng ea titration. Ho bohlokoa ho lula u ela hloko stoichiometry ea karabelo le ho sebelisa foromo ea motheo ea titration ka nepo ho fumana liphetho tse nepahetseng. Ho ikoetlisa ka ho tsoelang pele ka mefuta e fapaneng ea mathata ho tla thusa ho matlafatsa kutloisiso ea hau ea titration ea acid-base k'hemistri ea tlhahlobo.
