,
, 14 -
Redox
2
ectrode potentials
E
· dipping a metal into a solution ofits own ions is called
a
cell
half / electrode
o when a metal is dipped into a solution of its own metal ions
an equilibrium is set up
equilibrium lies to the left, the metal aquires a
o the
if
negative charse due to a build up ofelectrons on the
metal (negative potential
·
if equilibrium lies to the right, a positive charge builds up
as electrons have been used up to form metal (positive poventrial
· Cannotbe measured directly
o to measure, it needs to be connected to another half
cell
and the potential difference is measured
·
Combining the two makes an
electrochemical cell
· the standard hydrogen electrode is assisted potential O
of
· known as the primary standard
E
lectrochemical cell
· two cells joined together to give a complete circuit
o metals joined by a wire
·
solutions joined with a saltbridge
dapiece ofpaper soaked in unreactive ions) (e.s. KNO3
Standard Hydrogen Electrode
2H (aw) (2(g)
+
2e E0 +0.00V
-
+
=
Standard conditions
· cell concentration -
1.0 moldin-3 of all ions in halfequation
· cell temperature -
298K
·
Cell Pressure -
lOokPa only affects cell
gasses half
·
Standard Potential -
Go
Cell Notation
BO ↑ o ↓- Salt bride
lefthand cell right hand cell
-Phase boundre
- ROOR hishest oxidation
=
Curs) I am faal II zu (aa)(2n(s) state closest to centre
, 14 -
Redox
2
ectrode potentials
E
· dipping a metal into a solution ofits own ions is called
a
cell
half / electrode
o when a metal is dipped into a solution of its own metal ions
an equilibrium is set up
equilibrium lies to the left, the metal aquires a
o the
if
negative charse due to a build up ofelectrons on the
metal (negative potential
·
if equilibrium lies to the right, a positive charge builds up
as electrons have been used up to form metal (positive poventrial
· Cannotbe measured directly
o to measure, it needs to be connected to another half
cell
and the potential difference is measured
·
Combining the two makes an
electrochemical cell
· the standard hydrogen electrode is assisted potential O
of
· known as the primary standard
E
lectrochemical cell
· two cells joined together to give a complete circuit
o metals joined by a wire
·
solutions joined with a saltbridge
dapiece ofpaper soaked in unreactive ions) (e.s. KNO3
Standard Hydrogen Electrode
2H (aw) (2(g)
+
2e E0 +0.00V
-
+
=
Standard conditions
· cell concentration -
1.0 moldin-3 of all ions in halfequation
· cell temperature -
298K
·
Cell Pressure -
lOokPa only affects cell
gasses half
·
Standard Potential -
Go
Cell Notation
BO ↑ o ↓- Salt bride
lefthand cell right hand cell
-Phase boundre
- ROOR hishest oxidation
=
Curs) I am faal II zu (aa)(2n(s) state closest to centre
