Assertion: Following is the increasing order of non-metallic character `Si lt B lt C lt N lt F`.
Reason: Non-metallic character increases along a period and decreases down the group.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding Non-Metallic Character**:
- Non-metallic character refers to an element's tendency to accept electrons. The higher the tendency to accept electrons, the greater the non-metallic character.

**Hint**: Remember that non-metals tend to gain electrons, while metals tend to lose them.

2. **Periodic Table Positioning**:
- Look at the positions of the elements in the periodic table:
- Silicon (Si) is in Group 14.
- Boron (B) is in Group 13.
- Carbon (C) is in Group 14.
- Nitrogen (N) is in Group 15.
- Fluorine (F) is in Group 17.

**Hint**: Elements in the same group have similar properties, but their non-metallic character varies across periods.

3. **Trend Across a Period**:
- As you move from left to right across a period in the periodic table, the non-metallic character increases. This is because the elements become more electronegative and have a greater tendency to gain electrons.

**Hint**: Visualize the periodic table; elements on the right are generally more non-metallic.

4. **Trend Down a Group**:
- As you move down a group, the non-metallic character decreases. This is due to the increasing atomic size and the shielding effect, which makes it harder for the atom to attract additional electrons.

**Hint**: Think about how larger atoms have more electron shells, which can make it harder to attract new electrons.

5. **Determining the Order of Non-Metallic Character**:
- Based on the trends:
- Silicon (Si) has the least non-metallic character.
- Boron (B) is next.
- Carbon (C) follows.
- Nitrogen (N) has more non-metallic character.
- Fluorine (F) has the highest non-metallic character.

**Hint**: Order them based on the trends: Si < B < C < N < F.

6. **Conclusion**:
- The assertion states that the increasing order of non-metallic character is Si < B < C < N < F, which is correct.
- The reason provided explains that non-metallic character increases across a period and decreases down a group, which is also correct.

### Final Answer:
Both the assertion and the reason are correct, and the reason correctly explains the assertion.

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