Chemical Cells & Fuels Cells- Fuel Cells Flashcards
1
Q
in a fuel cell what reaction takes place
A
react a fuel such as hydrogen with oxygen or air
2
Q
for a hydrogen fuel cell what is the waste product produced
A
water
3
Q
what is the half equation for the negative electrode
A
2H2 —–> 4H+ + 4e-
4
Q
what is the half equation for the positive electrode
A
02 + 4H+ + 4e- ———> 2H2O
5
Q
what is the overall equation for the hydrogen fuel cell
A
2H2 + O2 ——> 2H20
6
Q
what are the positives of hydrogen fuel cells
A
- produce electricity for as long as you provide hydrogen
- do not get less efficient the longer they run
- source of drinking water (space craft)
7
Q
what are the problems with hydrogen fuel cells
A
- hydrogen is an explosive gas and so is difficult to store
- produce a relatively low potential difference so several are needed together
