Trifluoroacetic acid Trifluoroacetic acid Trifluoroacetic acid (TFA) is an organofluorine compound with the chemical formula CFCOH. It is a structural analogue of acetic acid with all three of the acetyl group’s hydrogen atoms replaced by fluorine atoms and is a colorless liquid with a vinegar like odor. TFA is a stronger acid than acetic acid, having an acid ionisation constant that is approximately 34,000 times higher, as the highly electronegative fluorine atoms and consequent electron-withdrawing nature of the trifluoromethyl group weakens the oxygen-hydrogen bond (allowing for greater acidity) and stabilises the anionic conjugate base. TFA is widely used in organic chemistry for
Pyrosilicic acid the original solution is converted to pyrosilicic acid, which persists for 10 minutes or more. Pyrosilicic acid can also be obtained by controlled hydrolysis of the corresponding organic ester, such as hexaethyl pyrosilicate, with dilute sulfuric acid. Pyrosilicic acid Pyrosilicic acid is the chemical compound with formula , or -O-. It is one of the silicic acids. It has never been isolated in pure form, but it is assumed to be present in solutions of silicon dioxide (silica) in water, in equilibrium with other silicic acids and silicate ions. The salts of pyrosilicic acid are called pyrosilicates, such as sodium