과망간산칼륨 산화환원 적정
Embed This Widget
Add the script tag and a data attribute to embed this widget.
Embed via iframe for maximum compatibility.
<iframe src="https://chemfyi.com/iframe/entity//" width="420" height="400" frameborder="0" style="border:0;border-radius:10px;max-width:100%" loading="lazy"></iframe>
Paste this URL in WordPress, Medium, or any oEmbed-compatible platform.
https://chemfyi.com/entity//
Add a dynamic SVG badge to your README or docs.
[](https://chemfyi.com/entity//)
Use the native HTML custom element.
KMnO₄를 이용한 철(II) 농도 결정
목표
자기 지시약인 표준 과망간산칼륨 용액으로 황산철(II) 용액을 적정하여 농도를 결정한다.
배경
Potassium permanganate is a powerful oxidizing agent that reacts with Fe2+ in acidic solution. MnO4- (purple) is reduced to Mn2+ (nearly colorless), so permanganate acts as its own indicator. The endpoint occurs when a single drop of excess KMnO4 produces a permanent pink/purple color.
안전 경고
- KMnO₄ stains skin and clothing permanently
- H₂SO₄ is corrosive
- Wear safety goggles and gloves throughout
- Wipe up KMnO₄ spills immediately
필수 개인 보호 장비
재료
-
Iron(II) sulfate solution (100 mL)Unknown concentration
-
Potassium permanganate (KMnO₄) (100 mL)0.02M standardized
-
Sulfuric acid (H₂SO₄) (50 mL)1M
-
Distilled water (200 mL)
장비
실험 절차
Rinse the burette with KMnO₄ solution, then fill to the 0 mL mark. Record the meniscus reading (read from the top of the meniscus since KMnO₄ is opaque).
Pipette exactly 25.0 mL of iron(II) sulfate solution into the Erlenmeyer flask.
Add 10 mL of 1M sulfuric acid to the flask to ensure acidic conditions.
Slowly add KMnO₄ from the burette while swirling. Each drop will decolorize as Fe2+ reduces MnO4-.
As the endpoint approaches, add drop by drop until a faint permanent pink/purple color persists for 30 seconds.
Record the final burette reading and calculate the volume used.
Repeat at least twice for concordant results.
Calculate the Fe2+ concentration using the balanced equation: MnO4- + 5Fe2+ + 8H+ → Mn2+ + 5Fe3+ + 4H2O.
예상 결과
The solution should transition from colorless to a persistent faint pink/purple at the endpoint. The 1:5 molar ratio of KMnO₄ to Fe2+ should yield an accurate concentration.
정리
Dilute waste solutions and dispose of KMnO₄ waste according to lab protocols. Rinse the burette thoroughly with water. Clean any stains with dilute acid or sodium sulfite.
세부 정보
- 카테고리
- Titrations
- 난이도
- Advanced (University)
- 소요 시간
- 50 분
- 예상 비용
- $18.00
- 단계
- 8
- 재료
- 4