Give the cell diagram for the voltaic cell that has the following overall equations:
a Ag+(aq) + Cu(s) → Ag(s) + Cu2+ (aq)
b Cu(s) + 2NO3−(aq) + 4H+(aq) → Cu2+ (aq) +2NO2(g) + 2H2O(l)
c 5IO4−(aq) + 2Mn2+(aq) + 3H2O(l) → 5IO3−(aq) +2MnO4−(aq) + 6H+(aq)
In a simple voltaic cell made from two metals and solutions of their ions, would the metal higher in
the activity series form the anode or the cathode of the cell?
a What is the purpose of the salt bridge?
b Give equations for the reactions in each half-cell
c What changes would be observed in each beaker?
.Copy and Label the diagram to show the following:
● the direction of electron flow through the external circuit
● the anode
● the cathode
● the positive electrode
● the negative electrode
● the direction of ion flow in the salt bridge
Cell notation is used as shorthand to describe voltaic
cells, for example:
Cu(s) | Cu2+ (aq) || H+(aq), Cr2O72−(aq), Cr3+ (aq) | Pt(s)
a What is the single vertical line used to represent?
b What is the double vertical line used to represent?
c What are the two electrodes made from in this
cell?
d Give the half-equations occurring at each
electrode.
e Give the overall equation for the cell.
Use the activity series in the IB data book to put the following voltaic cells in increasing order of the voltage they produce. Assume that any differences in conditions, such as concentration and temperature, can be ignored.
A Zn2+ + Mg → Mg2+ + Zn
B 2Cr3+ + 3Zn → 2Cr + 3Zn2+
C 3Mg2+ + 2Cr → 2Cr3+ + 3Mg
a Rechargeable batteries can be both charged and discharged. What do these two terms mean?
b In a rechargeable battery, does oxidation occur at the anode or cathode when the cell is being discharged?
a Give the equations when the lead–acid battery is being discharged.
b Using the equations, identify a suitable electrolyte in a lead–acid battery.
In a voltaic cell, in which direction do the electrons
flow in the external circuit?
c In a rechargeable battery, does oxidation occur at the anode or cathode when the cell is being charged?
d When a rechargeable battery is being discharged, is the anode negative or positive?
e When a rechargeable battery is being charged, is the anode negative or positive?
f Electrons flow in the external part of an electrochemical cell. What type of particle moves through the electrolyte of a cell?