Electric Cells Flashcards
What is a simple voltaic cell and what are its defects?
A simple voltaic cell consists of two different metals (electrodes) immersed in an electrolyte solution. The main defects include:
Polarization: Buildup of hydrogen gas on the cathode, reducing efficiency.
Local Action: Corrosion of the zinc electrode due to impurities.
How can the defects of a simple voltaic cell be corrected?
Polarization can be reduced by using a depolarizer like manganese dioxide.
Local Action can be minimized by using pure zinc or amalgamating the zinc with mercury.
What are the features and uses of the Daniel cell and Leclanché cell?
Daniel Cell: Uses a copper and zinc electrode with copper sulfate and zinc sulfate solutions, respectively. It is known for a steady voltage output.
Leclanché Cell: A carbon and zinc electrode with ammonium chloride as the electrolyte. The wet version is used in telegraphs, while the dry version is common in household batteries.
How should cells and batteries be maintained?
Regular maintenance includes:
- Checking and refilling the electrolyte in wet cells.
- Keeping terminals clean and free from corrosion.
- Ensuring proper charging cycles to extend battery life.
How are cells arranged in series and parallel, and what are the effects?
Series Arrangement: Cells connected end-to-end, increasing the total voltage (sum of individual voltages).
Parallel Arrangement: Cells connected side-by-side, maintaining the same voltage but increasing the total current supply.
What is the efficiency of a cell, and how is it determined?
The efficiency of a cell is the ratio of the useful electrical energy output to the total chemical energy consumed. It’s determined by factors like internal resistance and the type of chemical reactions occurring within the cell.
How can you solve problems involving series and parallel combinations of cells?
Use the formulas:
Series: Total voltage
𝑉_𝑡𝑜𝑡𝑎𝑙 = 𝑉1 + 𝑉2 + ⋯ +𝑉_𝑛
Parallel: Total current
𝐼_𝑡𝑜𝑡𝑎𝑙 = 𝐼1 + 𝐼2 + ⋯ + 𝐼_𝑛
while voltage remains the same across each cell.
How can you compare the advantages of lead-acid and Nickel-Iron accumulators?
Lead-acid accumulators offer high current and are cheaper, while Nickel-Iron accumulators are more durable and have a longer life but are less efficient and more expensive.
