1.
Pre-Lab Exercise Break apart the following redox reactions into the reduction and oxidation half
reactions. I. 2 Al(s) + 3 Cl2(g) ? 2AP+ + 6C1 a) Oxidation half-rxn: b) Reduction half-rxn: c)
How many moles of electrons are transferred in the balanced rxn? d) Species with increase in
oxidation number . e) Species with decrease in oxidation number: f. What is the line notation for
the overall reaction? 2. Mg(s) +2 HMg + H2(g) a) Oxidation half-rxn: b) Reduction half-rxn: c)
How many moles of electrons are trans ferred in the balanced rxn? d) Species with increase in
oxidation number: e) Species with decrease in oxidation number: f) What is the line notation for
the overall reaction?
Solution
1)
a) 2Al(s) - - - - - - > 2Al 3+
(aq) + 6e
b) 3Cl2(g) + 6e - - - - - - > 6Cl -
(aq)
c) 6moles of electrons
d) Al
e) Cl 2
f) Al(s)| Al 3+
(aq)||Cl 2 (g)|Cl -
(aq)|Pt(s)
2)
a) Mg(s) - - - - - - > Mg 2+
(aq) + 2e
b) 2H +
(aq) + 2e - - - - - - > H 2 (g)
c) 2moles of electrons
d) Mg
e) Cl 2

2.
f) Mg(s)|Mg 2+
(aq)||H +
(aq)|H 2 (g)|Pt(s)