The pH scale ranges from 0 to 14, with 7 being neutral. A pH less than 7 is acidic, and a pH greater than 7 is basic (alkaline). The concentration of hydroxide ions (OH–) increases as the pH value increases. Therefore, the pH with the highest concentration of OH– ions is 12.
Pairs of weak acids and bases that resist pH changes to maintain homeostasis are called buffers. Buffers are crucial in biological systems to maintain a stable pH environment, which is essential for proper cellular function.