Fuel Cells Flashcards
Fuel cells turn chemical energy (fuel) into…
useful electrical energy [with oxygen]
- what initially happens at the anode compartment?
Hydrogen enters the anode compartment and is oxidised by the anode (each H atom loses 1 electron to become a H+ ion)
Oxidisation of hydrogen at the anode compartment equation
H2 -> 2H+ + 2e
The hydrogen is the
fuel
the anode compartment is the _______ terminal
negative
Like in electrolysis the delocalised electron s from the hydrogen atoms flow from anode to _________
cathode - creating an electric current
The two electrodes are connected by a _____ that allows electrons to flow from ________ to ___________
wire
anode
cathode
In fuel cells, in between the electrodes, you can find the…
electrolyte - a solution that ions can move through - ionic substance
At the cathode compartment, air comes in through the _____ which obviously contains ______
inlet - oxygen
The oxygen molecules react with the ___ that have passed through the electrolyte and the _______ arriving via. the external circuit, forming _____
protons/ electrons/ H2O
negative anode half-equation
2H2 -> 4H+ + 4e
positive cathode half-equation
O2 + 4H+ + 4e -> 2H20
Overall reaction in the fuel cell which produces water as a waste product and releases useful energy
2H2 + O2 -> 2H20
positives of hydrogen fuel cells
Easy to maintain as there are no moving parts; small size; water is the only chemical product
negatives of hydrogen fuel cells
Very expensive to manufacture; need a constant supply of hydrogen fuel, which is a flammable gas
