PH temperature increases. Pure water is neutral, pH 7 at (25 °C), being neither an acid nor a base. Contrary to popular belief, the pH value can be less than 0 or greater than 14 for very strong acids and bases respectively. Measurements of pH are important in agronomy, medicine, chemistry, water treatment, and many other applications. The pH scale is traceable to a set of standard solutions whose pH is established by international agreement. Primary pH standard values are determined using a concentration cell with transference, by measuring the potential difference between a hydrogen electrode and a standard electrode such
Glutamic acid The radical corresponding to glutamate is called glutamyl. When glutamic acid is dissolved in water, the amino group (-) may gain a proton (), and/or the carboxyl groups may lose protons, depending on the acidity of the medium. In sufficiently acidic environments, the amino group gains a proton and the molecule becomes a cation with a single positive charge, HOOC-CH()-()-COOH. At pH values between about 2.5 and 4.1, the carboxylic acid closer to the amine generally loses a proton, and the acid becomes the neutral zwitterion OOC-CH()-()-COOH. This is also the form of the compound in the crystalline solid state.