Electrochemistry Lecture Notes

Jul 14, 2024

Electrochemistry Lecture Notes

Introduction

  • Lecturer: Tesh, Chemistry Educator
  • Topic: Electrochemistry
  • Common Fear: Many students find this chapter difficult and intimidating.

Structure of the Course

  • Two Parts: The chapter will be divided into two parts.
  • Schedule: A detailed schedule was shared in a video the previous day.
  • Coverage: The course will cover physical chemistry in 30 days.
  • Completion: Promise to regularly attend and follow the schedule for full coverage.

Class Schedule

  • Timings: Classes will usually be held at 10:00 AM.
  • Days: Generally on Monday, Thursday, and Saturday.

Main Topics in Electrochemistry

  1. Electrochemical Cell (Galvanic Cell) / Electrolytic Cell / Conductance: Three main parts of electrochemistry.
    • Electrochemical Cell: Also called Galvanic Cell.
    • Electrolysis: The process of causing a chemical reaction through electricity.
    • Conductance: The measure of how well a solution can conduct electricity.

Important Concepts

  • Anode and Cathode Charges: Incorrect Assumptions: Anode can be both positively and negatively charged depending on the type of cell (Electrochemical vs. Electrolysis).
  • Oxidation and Reduction: Always occurs at the anode and cathode respectively.
  • Movement of Electrons: Electrons move from the anode to the cathode in an electrochemical cell.

Practical Examples

  • Example of a Galvanic Cell: Zinc and Copper rods in respective solutions, creating a flow of electrons and generating current.
  • Salt Bridge: Completes the circuit and neutralizes charge buildup.

Key Notations and Equations

  • Representation of Cells: Anode followed by cathode notation with salt bridge indication.
  • Electrode Potentials: Calculated as the difference between reduction and oxidation potentials.
  • Nernst Equation: Used to calculate the cell potential under non-standard conditions.

Standard Electrode Potential

  • Hydrogen Electrode: Taken as the reference with a potential of 0V.

Relation Between Gibbs Free Energy and Cell Potential

  • Equation: ΔG° = -nFE°
  • Spontaneity: ΔG° negative implies a spontaneous process.

Concentration Cells

  • Concept: Uses the same electrodes with different concentrations.
  • Equation: Derived using Nernst equation for concentration cells.

Conclusion

  • Regular Attendance: Emphasized for better understanding and retention.
  • Test Series (NTS): Encouraged students to practice regularly using the test series for effective preparation.