General Chemistry Placement Practice Test 2025 - Free Chemistry Practice Questions and Study Guide

Electronegativity is defined as the tendency of an atom to attract electrons in a chemical bond. This property shows specific trends across the periodic table. As you move from left to right across a period, electronegativity increases due to the increasing positive charge in the nucleus. As the atomic number increases, the nucleus has a stronger attractive force on the electrons, making atoms more effective at attracting shared electrons in a bond.

Conversely, as you move down a group in the periodic table, electronegativity decreases. This decrease occurs because the atomic radius increases as you add additional electron shells. The increased distance between the nucleus and the outermost electrons results in a weaker attraction, meaning that the ability of the atom to attract bonding electrons diminishes.

Understanding these trends is critical in predicting how different elements will behave in chemical reactions, including whether bonds will be ionic or covalent. The trend identified in the answer reflects the fundamental behavior of elements regarding electronegativity across periods and groups in the periodic table.