Which of the following pairs of elements show similar set of oxidation state?

Options

A. `O^(16),O^(18)`
B. `Na,K`
C. `C, Be`
D. `Zn,Rb`

Explanation

To determine which pairs of elements show similar sets of oxidation states, we will analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Elements in Each Pair**:
- Option A: O16 and O18 (Isotopes of Oxygen)
- Option B: Sodium (Na) and Potassium (K)
- Option C: Carbon (C) and Beryllium (Be)
- Option D: Zinc (Zn) and Rubidium (Rb)

2. **Analyze Option A (O16 and O18)**:
- O16 and O18 are isotopes of oxygen, meaning they have the same number of electrons and the same atomic number (8), but different atomic masses (16u and 18u).
- Both isotopes of oxygen can exhibit the same oxidation states. Oxygen typically shows an oxidation state of -2.
- **Conclusion**: O16 and O18 both show a similar oxidation state of -2.

3. **Analyze Option B (Sodium and Potassium)**:
- Sodium (Na) and Potassium (K) are both alkali metals, located in Group 1 of the periodic table.
- Alkali metals consistently exhibit a +1 oxidation state.
- **Conclusion**: Sodium and Potassium both show the same oxidation state of +1.

4. **Analyze Option C (Carbon and Beryllium)**:
- Carbon (C) belongs to Group 14, while Beryllium (Be) belongs to Group 2.
- Beryllium typically shows a +2 oxidation state, while Carbon can show +4 or -4 oxidation states.
- **Conclusion**: Carbon and Beryllium do not show similar oxidation states.

5. **Analyze Option D (Zinc and Rubidium)**:
- Zinc (Zn) is a transition metal (D block), while Rubidium (Rb) is an alkali metal (Group 1).
- Zinc can exhibit multiple oxidation states (commonly +2), while Rubidium shows a +1 oxidation state.
- **Conclusion**: Zinc and Rubidium do not show similar oxidation states.

6. **Final Conclusion**:
- The pairs that show similar sets of oxidation states are:
- Option A: O16 and O18 (both -2)
- Option B: Sodium and Potassium (both +1)

### Final Answer:
The pairs of elements that show similar sets of oxidation states are **Option A (O16 and O18)** and **Option B (Sodium and Potassium)**.

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