Question
Chemistry Question on Redox reactions
Which of the following set of ions act as oxidising agents?
A
Ce4+ and Tb4+
B
La3+ and Lu3+
C
Eu2+ and Yb2+
D
Eu2+ and Tb4+
Answer
Ce4+ and Tb4+
Explanation
Solution
Oxidizing agents readily accept electrons and get reduced. Let's consider the common oxidation states of the given lanthanides:
- Ce: Common oxidation states are +3 and +4. Ce4+ readily accepts an electron to become Ce3+, acting as an oxidizing agent.
- Tb: Common oxidation states are +3 and +4. Tb4+ can be reduced to Tb3+, acting as an oxidizing agent.
La and Lu: These lanthanides predominantly exist in the +3 oxidation state and are not strong oxidizing agents.
Eu and Yb: These lanthanides exhibit +2 and +3 oxidation states. Eu2+ and Yb2+ are reducing agents (they tend to lose electrons and get oxidized).
Therefore, only Ce4+ and Tb4+ from the given options are good oxidizing agents.