Question

The highest possible oxidation states of uranium and plutonium, respectively, are

• A. $7$ and $6$
• B. $6$ and $4$
• C. $6$ and $7$
• D. $7$ and $5$
• E. $4$ and $6$

Hint:

Chemistry Tip: In actinides, variable oxidation states are more common than in lanthanides because 5f electrons are more available for bonding.

Answer 1

The Correct Option is C

Concept:
Uranium (U) and Plutonium (Pu) belong to the actinide series. Actinides show variable oxidation states because both $5f$, $6d$, and $7s$ electrons can participate in bonding.
Step 1: Electronic idea.
Actinides commonly show: $$+3,\ +4,\ +5,\ +6$$ Some also show higher states.
Step 2: Highest oxidation state of Uranium.
Uranium commonly reaches maximum: $$+6$$ Example: $$\text{UO}_2^{2+}$$ (uranyl ion)
Step 3: Highest oxidation state of Plutonium.
Plutonium can attain: $$+7$$ under strongly oxidising conditions.
Step 4: Match option.
Thus: $$\text{U} = +6,\qquad \text{Pu} = +7$$
Step 5: Final answer.
Hence correct option is: $$\boxed{\text{(C)}}$$ :contentReference[oaicite:1]{index=1}