Which of the following is a correct statement?

Options

A. Boron is diagonally related to silicon
B. Elements of third period are known as bridge elements
C. There are sixteen groups and seven periods in extended form of period table
D. Fluorine has higher electron affinity than Chlorine

Answer

To determine which of the statements is correct, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Analyze the First Option:**
- Statement: "Boron is diagonally related to silicon."
- **Explanation:** In the periodic table, boron (B) is located in Group 13, while silicon (Si) is in Group 14. Diagonal relationships occur between elements in different groups but in the same period or neighboring periods. Boron (Group 13) is indeed diagonally related to silicon (Group 14) as they are adjacent in the periodic table.
- **Conclusion:** This statement is **correct**.

2. **Analyze the Second Option:**
- Statement: "Elements of the third period are known as bridge elements."
- **Explanation:** The term "bridge elements" typically refers to the second period elements, not the third. The second period elements (Li, Be, B, C, N, O, F, Ne) are often considered bridge elements because they connect the metals and non-metals. Therefore, this statement is **incorrect**.

3. **Analyze the Third Option:**
- Statement: "There are 16 groups in the periodic table."
- **Explanation:** The modern periodic table consists of 18 groups, not 16. Therefore, this statement is also **incorrect**.

4. **Analyze the Fourth Option:**
- Statement: "Chlorine has higher electron affinity than chlorine."
- **Explanation:** This statement seems to have a typographical error as it compares chlorine with itself. However, if it meant to compare chlorine (Cl) with fluorine (F), it is known that fluorine has a higher electron affinity than chlorine. Therefore, this statement is **incorrect**.

### Final Conclusion:
The only correct statement among the options is the first one: **"Boron is diagonally related to silicon."**

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