Portable Power

Science 9
Electrical Principles
Portable Power
Topic 5
Read pages 300 – 307 in your textbook and answer the following questions.
1. Batteries transform ________________ energy directly into ________________.
3. A battery is just a series of connected ____________.
Electrochemical Cells
4. In any electrochemical cell, two metal ________________ are surrounded by an
______________, a substance that can conduct electricity.
5. Explain the difference between a “wet cell” and a “dry cell”.
6. In the space below, draw a diagram of a typical aluminum-copper wet cell. Label the different
parts and identify the path of the electrons. Use Fig 4.30 on page 301 to help you.
7. In every electrochemical cell, one ________________ is consumed.
8. Common “dry cells” sometimes leak when their zinc case (which forms one _______________)
is eaten away and the electrolyte paste oozes out of the cell.
9. The chemical reactions in a cell determines the ____________________________ (voltage) that
the cell can create.
10. Very few cells can produce more than _________. To obtain higher voltages, batteries contain
several _________ connected in _____________.
11. What is the difference between a PRIMARY cell and a SECONDARY cell?
12. What are the main components in a voltaic (electrochemical) cell? Describe the function of each
13. How do batteries differ from cells? What arrangement of three cells will result in the greatest
electric current? Which arrangement would result in the greatest longevity for the battery?
14. If you have five 1.5 V cells put together into a battery, what is the total voltage of the batter?
15. If your portable CD player requires 3.0 V of voltage to work, how many 1.5 V batteries will you
16. Batteries come in all shapes, sizes and varies in voltage. Beside each of the following situations,
list what kinds of features would you need in a battery for it?
Hearing aids –
Cell phones –
Mp3 player –
Environmentally friendly vehicles –
Digital cameras –
Laptop computers -