How is a base defined in terms of pH?

A base is defined in terms of pH as a substance that has a pH greater than 7. The pH scale ranges from 0 to 14, where values below 7 indicate acidity, values equal to 7 indicate neutrality, and values above 7 indicate basicity or alkalinity. When a substance has a pH greater than 7, it signifies that the concentration of hydroxide ions (OH⁻) is higher than that of hydrogen ions (H⁺), which characterizes the behavior of bases in aqueous solutions. Bases typically accept protons or donate electron pairs in chemical reactions, further supporting their classification as having a pH above 7.