FAQs on Quick Notes: Electrochemistry

Question 1

1. What is the difference between galvanic cells and electrolytic cells in electrochemistry?

Accepted Answer

Ans. Galvanic cells generate electrical current spontaneously through redox reactions, while electrolytic cells require external electrical energy to force non-spontaneous redox reactions. In galvanic cells, oxidation occurs at the anode and reduction at the cathode, producing usable electricity. Electrolytic cells reverse this process, consuming electrical energy to drive chemical changes. Understanding this distinction is crucial for NEET Chemistry Class 12 as both operate on opposite electrochemical principles and serve different practical applications.

Question 2

2. How do I calculate standard electrode potential and use it to predict cell reactions?

Accepted Answer

Ans. Standard electrode potential measures a species' tendency to lose or gain electrons, measured in volts against the standard hydrogen electrode. To predict spontaneous reactions, calculate the standard cell potential (E°cell) by subtracting the anode potential from the cathode potential. If E°cell is positive, the reaction occurs spontaneously. The Nernst equation helps determine cell potential under non-standard conditions. Refer to flashcards and mind maps on EduRev to visualise electrode arrangements and potential calculations for better retention.

Question 3

3. Why does the concentration of electrolyte affect the cell potential in real electrochemical setups?

Accepted Answer

Ans. Concentration changes alter the ion activity, which directly influences the cell potential through the Nernst equation. Higher electrolyte concentrations increase conductivity and reduce internal resistance, affecting the overall cell voltage. Temperature also modulates this relationship. Real galvanic and electrolytic cells deviate from standard conditions (1M concentration, 25°C, 1 atm pressure) because laboratory setups rarely maintain ideal parameters, making concentration effects observable and measurable in practice.

Question 4

4. What is Faraday's law of electrolysis and how do I use it to find the mass of substance deposited?

Accepted Answer

Ans. Faraday's law states that the mass of substance deposited during electrolysis is directly proportional to the charge passed and the molar mass of the substance. The relationship is: mass = (charge × molar mass) / (number of electrons × Faraday constant). One Faraday equals 96,500 coulombs. This law connects electrical quantities to chemical quantities, making it essential for solving electrolysis numericals in CBSE NEET Chemistry. Practice with numerical problems and worksheet solutions to master calculations.

Question 5

5. What are some real-world applications of electrochemistry that actually appear in NEET questions?

Accepted Answer

Ans. Electrochemistry powers batteries, fuel cells, electroplating, corrosion prevention, and metal refining-all common NEET topics. Electroplating uses electrolysis to coat objects with metal for protection and aesthetics. Batteries convert chemical energy into electrical energy for devices. Corrosion involves unwanted redox reactions that damage metals, preventable through cathodic protection. Understanding these applications helps students appreciate why electrochemical principles matter beyond theory, improving conceptual clarity for exam success.

Quick Notes: Electrochemistry

Chemistry Class 12