Explain formula "pH < 7 = acid" for pH < 7 = acid with 3 solved NCERT-style examples for Class 10 Science. (Class 10 science, Chapter: Acids, Bases and Salts)

pH < 7 indicates an acidic solution because the concentration of H⁺ ions is greater than 10⁻⁷ mol/L, which is the neutral point at 25°C.