In terms of periodic trends, how does electronegativity change across a period?

Electronegativity refers to the tendency of an atom to attract electrons within a chemical bond. As you move across a period from left to right on the periodic table, the electronegativity of elements generally increases. This trend is primarily due to the increase in nuclear charge without a corresponding increase in shielding effect from inner electron shells. As protons are added to the nucleus, the positive charge increases, enhancing the nucleus's ability to attract electrons.

Consequently, elements on the right side of the periodic table, such as fluorine and oxygen, are more electronegative compared to those on the left, like lithium and sodium. This increasing trend across a period is critical for understanding how elements bond and interact chemically.