2. Redox Flashcards
what is oxidation
loss of e-
what happens to the oxidation #/state when oxidation happens
increases
what does an oxidant cause
oxidation
what happens to an oxidising agent
it gets reduced
what happens in reduction
gain e-
what happens to the oxidation #/state in reduction
decreases
what does a reductant cause
reduction
what happens to the reducing agent
gets oxidised
what is the oxidation # of elements
0
what is the oxidation # of atom in monoatomic ion
charge on ion
what is the oxidation # of O2 in compound
-2
what is the oxidation # of O2 in peroxides
-1
what is the oxidation # of H in compound
+1
what is the oxidation # of H in metal hydrides
-1
what is the sum of oxidation # of atoms in a molecule
0
what is the sum of oxidation # of atoms in a polyatomic ion
charge on ion
how to balance equations
add H20 to balance Os
add H+ to balance Hs
add e- to balance charge
what is an electrode
electricity conductor
reactions occur on their surface
what is an anode - what occurs here
oxidation occur at this electrode
what is a cathode - what occurs here
reduction occur at this electrode
what are anions and where do they move towards
-
move towards anode
what are cation and where do they move towards
+
move towards cathode
how does a galvanic electrochemical cell work
2 half cells connected via
int circuit = ions through electrolyte to maintain charge
ext circuit = e- move through wire between electrodes
causes electric current to flow via 2 different metals resulting in e- transfer
how does an electrolytic cell work
electrolysis where power supply forces oxidation and reduction via e- movement in ext circuit
electrolyte allows ion movement = int circuit
if the standard reduction potential is further up what does this mean
more easily reduced
stronger oxidant
if the overall E* is + what does this mean
spontaneous
when calculating E* cells for oxidated species what must you do
flip + and negative signs for oxidised species
