Electronegativity is a measure of an atom’s ability to attract shared electrons toward itself in a chemical bond. It reflects how strongly an atom “pulls” on electrons when it forms molecules with other atoms.

In the periodic table, electronegativity generally:

• Increases across a period (left to right), as atoms have more protons and a stronger pull on electrons
• Decreases down a group (top to bottom), as outer electrons are farther from the nucleus and more shielded

The most electronegative element is fluorine, assigned a value of 3.98 on the Pauling scale.

Electronegativity differences between atoms determine the type of bond:

• Small or no difference → nonpolar covalent bond
• Moderate difference → polar covalent bond
• Large difference → ionic bond

Understanding electronegativity is crucial for predicting molecular polarity, reactivity, and bond strength, making it a central concept in chemical bonding and molecular behavior.