The scientist who developed the periodic table is Dmitri Mendeleev. In 1869, Mendeleev published his version of the periodic table, organizing the chemical elements by increasing atomic mass and highlighting periodic trends based on properties. His work allowed for the prediction of the existence and properties of undiscovered elements, which later were confirmed. Mendeleev’s periodic table laid the groundwork for modern chemistry and established a systematic way to understand the relationships between elements. His contributions earned him recognition as one of the founding figures of the field and are celebrated in the scientific community.