Practice using LEO says GER to track electron transfer in oxidation-reduction reactions.
Read each problem carefully. Use LEO says GER: loss of electrons is oxidation, gain of electrons is reduction. Show your work in the space provided.
Identify oxidation, reduction, electron flow, and redox agents
Chemistry - Grade 9-12
- 1
In the half-reaction Zn -> Zn2+ + 2e-, is zinc oxidized or reduced? Explain using LEO says GER.
- 2
In the half-reaction Cu2+ + 2e- -> Cu, is copper ion oxidized or reduced? Explain using LEO says GER.
- 3
For the reaction Zn + Cu2+ -> Zn2+ + Cu, identify the substance oxidized and the substance reduced.
- 4
Write the oxidation half-reaction for magnesium changing into magnesium ions in the reaction Mg + Cl2 -> MgCl2.
- 5
Write the reduction half-reaction for chlorine gas changing into chloride ions in the reaction Mg + Cl2 -> MgCl2.
- 6
In the reaction 2Na + Cl2 -> 2NaCl, which reactant is the reducing agent? Explain your answer.
- 7
In the reaction 2Na + Cl2 -> 2NaCl, which reactant is the oxidizing agent? Explain your answer.
- 8
Assign oxidation numbers to iron and oxygen in Fe2O3. Then state whether iron is more oxidized in Fe2O3 than in elemental Fe.
- 9
For the reaction Fe + CuSO4 -> FeSO4 + Cu, identify what is oxidized, what is reduced, the oxidizing agent, and the reducing agent.
- 10
A student says, "If a substance is oxidized, it must gain oxygen, not lose electrons." Correct the statement using LEO says GER.
- 11
Balance the electron transfer between these two half-reactions: Al -> Al3+ + 3e- and Ag+ + e- -> Ag. How many silver ions are reduced for each aluminum atom oxidized?
- 12
Use LEO says GER to explain the electron transfer in this reaction: 2Al + 3Cu2+ -> 2Al3+ + 3Cu.