The dry cell
Cell with a thick paste instead of a liquid.
Easy to carry
A Voltaic cell has a liquid inside, so it is not convenient for everyday use.
How could we change the cell to make it easy to use and carry?
What this lesson covers
The idea
A dry cell has a thick moist paste as electrolyte instead of a liquid; its zinc container is the negative terminal and a central carbon rod with a metal cap is the positive terminal; it is single use.
Easy to carry
A Voltaic cell has a liquid inside, so it is not convenient for everyday use.
How could we change the cell to make it easy to use and carry?
- Use a thick paste instead of a liquid
- Use a bigger glass jar
- Fill it with sand
Look inside
Tap each part of the cut open dry cell to see what it does.
Why it is called dry
The electrolyte of a dry cell is a thick moist paste, not a liquid. The zinc container is the negative terminal. The carbon rod with its metal cap is the positive terminal.
A dry cell has a thick moist paste as its electrolyte, not a liquid. Its zinc container is the negative terminal and a carbon rod with a metal cap is the positive terminal. It is a single use cell.
- Part | Job
- Zinc container | Negative terminal
- Carbon rod with metal cap | Positive terminal
- Thick moist paste | Electrolyte
Notes
A dry cell has a thick moist paste as electrolyte. The zinc container is negative. The carbon rod with a metal cap is positive. It is a single use cell.
Check yourself
Why is a dry cell called 'dry'?
The negative terminal of a dry cell is its …
The positive terminal of a dry cell is the …
A dry cell is a single use cell. What does that mean?
- It never gets wet outside. The name is about the electrolyte. It is a paste, not a liquid.
- Its electrolyte is a thick moist paste, not a liquid — correct. Yes!
- It has no electrolyte at all. It does have an electrolyte. It is a thick moist paste.
- carbon rod. The carbon rod with its metal cap is the positive terminal.
- paste. The paste is the electrolyte. It is not a terminal.
- zinc container — correct. Yes!
- carbon rod with a metal cap — correct. Yes!
- zinc container. The zinc container is the negative terminal.
- paste. The paste is the electrolyte. It is not a terminal.
- It can be recharged many times. That describes a rechargeable battery. A dry cell cannot be recharged.
- Once it is used up, it has to be disposed of — correct. Yes!
- It works for one second. Single use means it is used up once. Then it is thrown away properly.