electrode potentials Flashcards
what is the anticlockwise rule
most negative electrode potential goes on top
cell potential =
E of bottom - E of top
why might a reaction not occur despite cell potential saying it can
activation energy may be too high
not standard conditions
how to balance oxygen in half equations
add water
how to balance hydrogens in half equations
add hydrogen ions
how to balance half equation if conditions are alkaline
add OH-
how do we measure potential difference
a high resistance voltmeter to stop the flow of electrons from where there is many to where there is few
what is current
how many electrons pass a certain point in a second
what does a salt bridge do
overall charge s neutral
what charge is the anode
negative as this is where oxidation occurs
rules to follow
most negative electrode potential on left
this is the anode
electrons flow from anode to cathode
charge of cathode
positive
standard conditions
standard hydrogen electrode over a platinum electrode
100kPa
in solution of its ions at 1 mol
298K
define standard electrode potential
potential difference of the half cell combined with the standard hydrogen electrode
298K 1mol dm-3 1 atm
MPBOA
more positive (standard electrode potential) better oxidising agent
