1.4 - Cells and Batteries

Question 1

What is an electrochemical cell?

Answer 1

A package of chemicals that react to produce a small amount of electricity

Question 2

What is an electrolyte?

Answer 2

Contained in an electrochemical cell, it is a paste or liquid that conducts electricity (contains chemicals that form ions)

Question 3

What happens within primary cells?

Answer 3

Chemical reactions that cannot be reversed

Question 4

What are dry cells?

Answer 4

• Used in portable devices
• A paste electrolyte reacts with two metals called electrodes; one becomes positively charged (cathode) and the other becomes negatively charged (anode)
• Electrons flow from the negative terminal through the device and back to the positive terminal

Question 5

What are wet cells?

Answer 5

• Used in car batteries
• A liquid electrolyte (usually an acid) reacts with two electrodes; one becomes positively charged and the other negatively charged
• Electrons flow from the negative terminal, through the device and back to the positive terminal
• One electrode (negative) is slowly eaten away.

Question 6

What are secondary/rechargeable cells?

Answer 6

• In these cells, the chemical reactions can be reversed using an electrical source that restores the reactants
  
  • Ex. Ni-Cd (nickel oxide and cadmium) batteries
  • Electrodes still wear out over time

Question 7

What is a battery?

Answer 7

More than one cell connected together in a sealed case with only two terminals

Question 8

What is electrochemistry?

Answer 8

The study of chemical reactions involving electricity

Question 9

What is electrolysis?

Answer 9

A process that uses an electric current to split molecules into their elements.
- Ex. Producing chlorine for drinking water

Question 10

What is electroplating?

Answer 10

Involves using electricity to coat a thin layer of metal onto an object
- Ex. Plating a spoon with silver