Question

The correct order of the non-metallic character among the elements B, C, N, F and Si is

• A. B>C>Si>N>F
• B. Si>C>B>N>F
• C. F>N>C>B>Si
• D. F>N>C>Si>B

Hint:

- Non-metallic character increases across a period (left to right). - Non-metallic character decreases down a group. - Electronegativity is a good indicator of non-metallic character (higher electronegativity means more non-metallic). - Fluorine (F) is the most electronegative and most non-metallic element. - Metalloids (like B, Si) have intermediate properties.

Answer 1

The Correct Option is C

Non-metallic character generally increases across a period (from left to right) and decreases down a group in the periodic table.
This is related to electronegativity and ionization energy.
Elements that readily gain electrons to form negative ions or share electrons in covalent bonds are more non-metallic.
The given elements are: - Boron (B): Group 13, Period 2 - Carbon (C): Group 14, Period 2 - Nitrogen (N): Group 15, Period 2 - Fluorine (F): Group 17, Period 2 - Silicon (Si): Group 14, Period 3 Comparing elements in Period 2 (B, C, N, F): Non-metallic character increases from left to right: B<C<N<F.
So, F is the most non-metallic, followed by N, then C, then B.
Now compare with Silicon (Si).
Silicon is in the same group as Carbon (Group 14) but in Period 3.
Carbon is in Period 2.
Non-metallic character decreases down a group.
So, Carbon (C) is more non-metallic than Silicon (Si).
Silicon is a metalloid, having properties intermediate between metals and non-metals.
Boron is also considered a metalloid but is generally less metallic than Silicon.
Combining these trends: Fluorine (F) is the most non-metallic among the given elements.
Nitrogen (N) is next.
Carbon (C) is next.
Between Boron (B) and Silicon (Si): - Boron is in Period 2, Group 13.
- Silicon is in Period 3, Group 14.
Carbon is more non-metallic than Boron.
Silicon is less non-metallic than Carbon.
Comparing B and Si: Electronegativity values (Pauling scale): B: 2.
04 C: 2.
55 N: 3.
04 F: 3.
98 Si: 1.
90 Higher electronegativity generally corresponds to higher non-metallic character.
Based on electronegativity: F>N>C>B>Si.
So the order of decreasing non-metallic character is: F>N>C>B>Si.
This matches option (3).