electrochemistry and cells Flashcards
standard conditions for measuring electrode potential (3)
- conc. of solutions = 1.0 mol/dm3
- 298K
- 100kpa / 1atm
standard cell for comparison (primary)
- electrode used
hydrogen cell
- platinum
metal dipping into solution =
half cell
if eq. lies to the left, charge will be … due to … making the potential …
negative
due to build up of electrons on metal
negative
if eq. lies to the right, charge will be … due to … making the potential … ??
positive
as electrons used up to form the metal
positive
more reactive metals tend to have ….. potentials
negative
positive potential = … hand electrode = ….
right
cathode
emf of cell =
E right - E left
secondary standard
one which has been calibrated against primary standard
anode…
oxidation
negative
which way do reduction reactions go
left to right
which what type of reaction is the more negative V
oxidation
which way do oxidation reactions go
right to left
what is always needed for fuel cells?
- what can be used?
- oxygen!!
- hydrogen/alternatives
set up used to investigate potential of an electrode
- use standard hydrogen electrode
- salt bridge - potassium nitrate
for a positive potential difference, electrons moe from…. to …
left
right