The most electronegative element among the following is:

Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons toward itself. It is one of the most important periodic properties of elements, and it plays a key role in determining the nature of chemical bonds, molecular polarity, and reactivity.

Among the elements listed — antimony (Sb), nitrogen (N), arsenic (As), and phosphorus (P) — all belong to Group 15 (the nitrogen family) of the periodic table. Within this group, the trend of electronegativity decreases from top to bottom because atomic size increases, and the attraction between the nucleus and bonding electrons becomes weaker.

Here’s the approximate electronegativity order on the Pauling scale:

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  Nitrogen (N): 3.0

  
  


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  Phosphorus (P): 2.1

  
  


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  Arsenic (As): 2.0

  
  


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  Antimony (Sb): 1.9

  
  

Nitrogen sits at the top of Group 15 and has the smallest atomic radius and highest effective nuclear charge among these elements. These factors allow nitrogen to attract shared electrons more strongly in a covalent bond. Because of its high electronegativity, nitrogen forms polar covalent bonds with elements like hydrogen (as in NH₃) and carbon (as in organic amines).

In contrast, antimony and arsenic are much larger atoms with more electron shells, which shield the nuclear charge and reduce their ability to attract electrons effectively. This is why their electronegativities are significantly lower.

The concept of electronegativity also helps explain other periodic behaviors:

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  The metallic character increases down the group as electronegativity decreases.

  
  


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  The non-metallic character is most pronounced at the top, where nitrogen resides.

  
  

Therefore, among the given options, Nitrogen (N) is the most electronegative element due to its small size, high effective nuclear charge, and strong electron-attracting ability.