Maximum oxidation state of uranium and plutonium are respectively :

Options

A. 4 and 6
B. 5 and 6
C. 6 and 7
D. 6 and 8

Answer

To determine the maximum oxidation states of uranium and plutonium, we can follow these steps:

### Step 1: Identify the elements
We are looking at uranium (U) and plutonium (Pu), which are both actinides and belong to the f-block of the periodic table.

### Step 2: Determine the electron configuration
- **Uranium (U)** has the atomic number 92. Its electron configuration is:
\[ [Rn] 5f^3 6d^1 7s^2 \]
- **Plutonium (Pu)** has the atomic number 94. Its electron configuration is:
\[ [Rn] 5f^6 7s^2 \]

### Step 3: Count the valence electrons
- For uranium, the outermost shell (6th shell) has:
- 2 electrons in 7s
- 1 electron in 6d
- 3 electrons in 5f
- Total: 6 electrons
- For plutonium, the outermost shell (7th shell) has:
- 2 electrons in 7s
- 6 electrons in 5f
- Total: 8 electrons

### Step 4: Determine the maximum oxidation state
The maximum oxidation state corresponds to the maximum number of electrons that can be lost from the outermost shell:
- **Uranium** can lose all 6 of its outermost electrons (2 from 7s, 1 from 6d, and 3 from 5f), giving it a maximum oxidation state of +6.
- **Plutonium** can lose all 8 of its outermost electrons (2 from 7s and 6 from 5f), giving it a maximum oxidation state of +8.

### Conclusion
Thus, the maximum oxidation states of uranium and plutonium are +6 and +8, respectively.

### Final Answer
The maximum oxidation states of uranium and plutonium are respectively: **6 and 8**.

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