농도 전지

농도 차이로 전압 발생시키기

Electrochemistry Advanced (University) 45 분 ~$18.00

목표

농도가 다른 구리 반전지를 사용한 농도 전지를 구성하고, 전지 전위에 대한 네른스트 방정식의 예측을 검증한다.

배경

A concentration cell generates voltage from the difference in concentration between two otherwise identical half-cells. According to the Nernst equation, the EMF depends on the logarithm of the concentration ratio. This experiment demonstrates that even without different metals, a potential difference arises from entropy-driven mixing.

안전 경고

  • Copper sulfate is toxic
  • Wear gloves when handling solutions

필수 개인 보호 장비

goggles gloves lab_coat

재료

  • Copper(II) sulfate (CuSO₄) (200 mL total)
    Prepare 0.01M and 1M solutions
  • Copper strips (2) (2 pieces)
    Identical, sanded clean
  • Potassium nitrate salt bridge (1)
    Saturated KNO₃ in agar

장비

Two 250 mL beakers High-impedance voltmeter Wires with alligator clips Sandpaper Volumetric flasks

실험 절차

1

Prepare two CuSO₄ solutions: 100 mL of 1.0M and 100 mL of 0.01M.

5 분 Wear gloves
2

Sand both copper strips until shiny and rinse with distilled water.

3 분
3

Pour the dilute (0.01M) CuSO₄ into one beaker and the concentrated (1.0M) into the other.

2 분
4

Place one copper strip in each beaker. Connect with the salt bridge.

3 분
5

Connect the voltmeter. The dilute side is the anode (negative terminal). Measure the EMF.

5 분
6

Calculate the predicted EMF using the Nernst equation: E = (RT/nF) ln(C_high/C_low) = (0.0257/2) ln(100) = 0.059 V at 25°C.

5 분
7

Compare measured and theoretical values. Discuss sources of deviation.

5 분

예상 결과

The cell should produce approximately 0.05-0.06 V. The Nernst equation predicts E = (0.02569 V / 2) x ln(1.0/0.01) = 0.059 V at 25°C. Measured values may be slightly lower due to junction potentials.

정리

Dispose of copper sulfate waste in designated containers. Rinse and store copper strips. Clean salt bridge.

세부 정보

카테고리
Electrochemistry
난이도
Advanced (University)
소요 시간
45 분
예상 비용
$18.00
단계
7
재료
3

더 많은 실험

황산구리 전기분해 50 min 다니엘 전지 제작 45 min 활동도 순서 확인 30 min 레몬 전지 20 min 구리 전기도금 60 min 물의 전기분해 40 min 볼타 전지 기전력 측정 60 min 녹 방지 방법 비교 30 min

Frequently Asked Questions

What is the objective of 농도 전지?
농도가 다른 구리 반전지를 사용한 농도 전지를 구성하고, 전지 전위에 대한 네른스트 방정식의 예측을 검증한다.
How difficult is 농도 전지?
This experiment is rated as Advanced (University). It takes approximately 45 minutes to complete.
What safety precautions are needed for 농도 전지?
Key safety precautions include: Copper sulfate is toxic; Wear gloves when handling solutions.
What materials are needed for 농도 전지?
The main materials required are: Copper(II) sulfate (CuSO₄), Copper strips (2), Potassium nitrate salt bridge.
What results should I expect from 농도 전지?
The cell should produce approximately 0.05-0.06 V. The Nernst equation predicts E = (0.02569 V / 2) x ln(1.0/0.01) = 0.059 V at 25°C. Measured values may be slightly lower due to junction potentials.