Redox and electrode potentials Flashcards
Using E values, how do you know the best oxidising agent?
Most positive E value (normally top right)
Using E values, how do you know the best reducing agent?
Most negative E value (normally bottom left)
How do you combine half equations?
Balance electrons
Balance charges
Balance atoms
Put together
How do you work out E cell?
Most positive - Most negative
What are the 2 limitations of predictions using E cell data?
May have a too high activation energy to actually occur
May be in different concentrations to the standard condition of 1 mol dm⁻³
Why would concentration limit the predictions using E cell data?
Shifts the position of equilibrium so it would change the electrons and therefore, the voltage/ E
Definition of standard electrode potential
The E.M.F of a half cell compared with the standard hydrogen half cell under standard conditions of 298K, 100kPa and 1 moldm⁻³
What electrode is used if there isn’t a solid in the half equation?
Platinum (Pt)
What is the purpose of a platinum electrode?
Inert, allows the electrons to move
Which direction do electrons flow in a cell?
Most negative to most positive
How do you combine 2 half equations using electrode potentials?
Balance electrons
Most positive stays the same (electrons on left)
Most negative swaps round (electrons on right)
