redox

electrochemical cells, galvanic (voltaic) cell, electrolytic cell

generates electrical energy frm chemical reacitons

• galvanic: produces frm spotanteous reaction

• electrolytic: consumes current to drive non spont reaction

cathode and anode as electrodes

• CATHODE: REDUCTION

• ANODE: OXIDATION

• connected with salt bridge

cell notation

anode || cathode where | represences phase boundary and || represents two phase boundaries

standard cell potention

E cath - E anode

three criteria for reference electrode

easy to construct

reversible

highly reproducible in behaviour

SHE

standard hydrogen electrode

• half cell that consists of inert platinum immersesd in 1 M hcl with hydrogen gas at 1 bar

• E0 = 0 V

for a SHE eelctrode if E cell is > 0 it is _____ and if its < 0 it is ____

E cell is spontaneus reduction greater than zero, non spontaneous oxidation less than zero

for SHE, the potentials reported on the eelctrodes are ____ potentials

reduction because she is always on the left side

as ionic strength increases what happens to activity coeffiecient?

decrease and at very high ionic stregth it will increase more than one

• activity coeffi

in dilute soltuons the activity coeficient is what

independent of the nature of the electrolyte