Storage & Fuel Cells

Question 1

What are some uses of primary cells?

Answer 1

• used for low-current, long-storage devices as they are single use only

Question 2

What are some uses of secondary cells?

Answer 2

• car batteries, radios, torches and modern appliances as they are rechargeable due to the cell reactions being able to be reversed when they are being charged to regenerate chemicals in the cell

Question 3

What are fuel cells?

Answer 3

Use energy from the reaction of a fuel with oxygen to create a voltage

Question 4

What are some key features of fuel cells?

Answer 4

• do not have to be recharged
• operate continuously provided that fuel and oxygen are supplied

Question 5

Why are hydrogen fuel cells seen as being better for the environment?

Answer 5

Produce no CO2 (fossil fuels)

Question 6

Compare alkali hydrogen fuel cells and acid hydrogen fuel cells.

Answer 6

Similarities:
- same overall equation: H2 + 1/2O2 —> H2O
- same overall electrode potential: 1.23V

Differences:
- Alkali uses OH- ions and acid uses H+ ions