FORMATIVE TEST- Galvanic cells and balancing equations in acidic conditions Name: _________________
1.
Galvanic cell setup
A student creates a galvanic cell from Fe 2+ /Fe 3+ and Zn/Zn 2+ half cells. a.
Write the oxidation half equation.
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(1 mark) b.
Write the overall reaction equation.
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(1 mark) c.
Identify i.
The reducing agent
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(1 mark) ii.
A suitable salt-brige solution
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(1 mark) iii.
The expected EMF of the cell
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(1 mark) d.
In the beakers below, draw the galvanic cell. Label the anode, cathode, the polarity of the electrodes, the electrode and solution materials, and indicate the direction of electron flow in the external circuit.
(3 marks) e.
After the galvanic cell is setup and producing a potential difference, a student dunks a piece of Aluminium solid into the Fe 2+ /Fe 3+ half-cell. The galvanic cell current suddenly drops. Explain why this observation is made using your knowledge of the electrochemical series.
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(1 mark)

2.
Reaction equations a) Write the half-equations and overall equations for the below redox reactions and note the expected observations.
(Use the electrochemical series to predict the products of these reactions) i.
Cobalt solid reacting with Bromine liquid (Br
2
).
Reduction: ______________________________________________________________________________
Oxidation: ______________________________________________________________________________
Overall: ______________________________________________________________________________
Observations: ___________________________________________________________________________
(4 marks) ii.
Cl
2
gas reacted in hydroxide ions (OH ) in the presence of a pH indicator
Reduction: ______________________________________________________________________________
Oxidation: ______________________________________________________________________________
Overall: ______________________________________________________________________________
Observations: ___________________________________________________________________________
(4 marks) b) Write the half-equations and overall equations for the below redox reaction. Predict products using acidic balancing rules i.
Permanganate ions (MnO
4
) reacting with Lead solid, forming Manganese ions and Lead ions
Reduction: ______________________________________________________________________________
Oxidation: ______________________________________________________________________________
Overall: ______________________________________________________________________________
(3 marks) c) Consider direct redox reactions. i.
Predict which of the below reactants will react by placing a tick in the box.
Fe 3+ (aq) Sn 4+ (aq) Al 3+ (aq)
Au (s)
Ni (s)
Li (s) ii.
Predict which of the above combinations of reactants will produce the largest voltage if a galvanic cell was setup. Show a calculation to support your answer.
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( 2 marks)