Answer:
pH is a measurement of the acidity/basicity of a solution based on the hydrogen ion concentration.
The pH has a scale from 0 to 14. A solution with a pH of 7 is said to be neutral (neither acidic nor basic). These solutions have an equal concentration of H⁺ and OH⁻ ions. A pH below 7 is acidic (H⁺ > OH⁻) and a pH above 7 is basic (H⁺ < OH⁻).
The equation used to calculate the pH is:
pH = -log[H⁺]