濃淡電池

濃度差から電圧を発生させる

Electrochemistry Advanced (University) 45 分 ~$18.00

目的

異なる濃度の銅半電池を用いた濃淡電池を構築し、電池電位に関するネルンスト式の予測を検証する。

背景

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.

安全上の警告

  • Copper sulfate is toxic
  • Wear gloves when handling solutions

必要なPPE

goggles gloves lab_coat

材料

  • 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

器具

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

手順

1

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

5 分 Wear gloves
2

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

3 分
3

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

2 分
4

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

3 分
5

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

5 分
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 分
7

Compare measured and theoretical values. Discuss sources of deviation.

5 分

予想される結果

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.

後片付け

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

詳細

カテゴリ
Electrochemistry
難易度
Advanced (University)
所要時間
45 分
推定費用
$18.00
ステップ数
7
材料
3

その他の実験

ダニエル電池の製作 45 min ボルタ電池の起電力測定 60 min レモン電池 20 min 水の電気分解 40 min 活動列の確認 30 min 硫酸銅の電気分解 50 min 銅電気めっき 60 min 防錆方法の比較 30 min

Frequently Asked Questions

What is the objective of 濃淡電池?
異なる濃度の銅半電池を用いた濃淡電池を構築し、電池電位に関するネルンスト式の予測を検証する。
How difficult is 濃淡電池?
This experiment is rated as Advanced (University). It takes approximately 45 minutes to complete.
What safety precautions are needed for 濃淡電池?
Key safety precautions include: Copper sulfate is toxic; Wear gloves when handling solutions.
What materials are needed for 濃淡電池?
The main materials required are: Copper(II) sulfate (CuSO₄), Copper strips (2), Potassium nitrate salt bridge.
What results should I expect from 濃淡電池?
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.