Which of the following pairs contain metalloid elements in the periodic table ?

Options

A. Na and K
B. F and C1
C. Ca and Mg
D. As and Si

Explanation

To determine which of the following pairs contain metalloid elements, we first need to understand what metalloids are and where they are located in the periodic table.

### Step-by-Step Solution:

1. **Define Metalloids**: Metalloids are elements that have properties intermediate between metals and non-metals. They are typically semiconductors of electricity and have a mix of metallic and non-metallic properties.

2. **Identify the Location of Metalloids**: In the periodic table, metalloids are found in the p-block, specifically in groups 13 to 18. Common examples of metalloids include silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), and tellurium (Te).

3. **Analyze the Given Pairs**:
- Check each pair provided in the question to see if both elements in the pair are metalloids.
- For instance, if the pairs are (Si, Ge), (Na, Cl), (As, Sb), etc., we need to identify the nature of each element.

4. **Evaluate Each Pair**:
- **Pair 1**: (Si, Ge) - Both silicon and germanium are metalloids.
- **Pair 2**: (Na, Cl) - Sodium is a metal and chlorine is a non-metal (halogen).
- **Pair 3**: (As, Sb) - Both arsenic and antimony are metalloids.
- **Pair 4**: (Mg, Ca) - Both magnesium and calcium are metals.

5. **Conclusion**: The pairs that contain only metalloid elements are (Si, Ge) and (As, Sb).

### Final Answer:
The pairs that contain metalloid elements are (Si, Ge) and (As, Sb).

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