Explanation

• pH is a measure of the concentration of hydrogen ions (H+) in an aqueous solution.
• The term "pH" was coined by the Danish chemist Søren Sørensen in 1909, and it stands for "power of hydrogen". It is defined as the negative logarithm of the concentration of hydrogen ions in a solution: pH = -log[H+]
• A pH of 7 is neutral, while values below 7 are acidic and above 7 are basic.