The largest atomic radius will be of

Options

A. Be
B. Na
C. F
D. Mg

Answer

To determine which element has the largest atomic radius among beryllium, sodium, fluorine, and magnesium, we can follow these steps:

### Step 1: Identify the Position of Each Element in the Periodic Table
- Beryllium (Be) is in Group 2, Period 2.
- Sodium (Na) is in Group 1, Period 3.
- Fluorine (F) is in Group 17, Period 2.
- Magnesium (Mg) is in Group 2, Period 3.

### Step 2: Understand Atomic Radius Trends
- Atomic radius decreases from left to right across a period due to increasing effective nuclear charge, which pulls electrons closer to the nucleus.
- Atomic radius increases from top to bottom in a group because additional electron shells are added, which increases the distance between the nucleus and the outermost electrons.

### Step 3: Compare the Elements
- **Beryllium (Be)**: Being in Period 2 and Group 2, it has a relatively small atomic radius.
- **Fluorine (F)**: Also in Period 2 but in Group 17, it has an even smaller atomic radius than beryllium due to its higher effective nuclear charge.
- **Magnesium (Mg)**: In Period 3 and Group 2, it has a larger atomic radius than beryllium because it has an additional electron shell.
- **Sodium (Na)**: In Period 3 and Group 1, it has the largest atomic radius among these elements because it is in Group 1, which has a larger radius compared to Group 2 elements in the same period.

### Step 4: Conclusion
Based on the trends and comparisons, sodium (Na) has the largest atomic radius among the given options.

### Final Answer
The largest atomic radius will be of **sodium (Na)**.

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