Electrochemical cells and potentials Flashcards
What is the golden rule for cell potentials?
More negative E -> LHS so is oxidised.
What is a salt bridge made up of?
Tube of unreactive ions that can move between the solutions to allow ions to flow.
What are the standard conditions?
298K, 100kPa, 1 mol dm-3
What happens when you increase the concentration of a half cell?
Position of equilibrium moves in one direction. The EMF changes relative to which direction this moves.
What happens if the conc of the negative electrode solution is increased?
The rate will increase in the reduction direction and so the potential of this half cell will increase.
What happens if the conc of the positive electrode is increased?
The rate will increase in the reduction direction and so the potential of this half cell will increase.
What is the LHS half equation for lithium ion battery?
Li -> Li+ + e-
What is the RHS half equation for the lithium ion battery?
Li+ + e- + CoO2 -> Li[CoO2]
Overall equation for lithium ion battery.
Li + Li+ +CoO2 -> Li+ + Li[CoO2]
Why are hydrogen fuel cells more environmental than internal combustion engines?
H2O is the ONLY product.
Why are hydrogen fuel cells not actually that great for the environment?
H2 is produced by electrolysis. The energy for this is normally from burning fossil fuels which releases CO2.
