DNA DNA Deoxyribonucleic acid (; DNA) is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acids; alongside proteins, lipids and complex carbohydrates (polysaccharides), nucleic acids are one of the four major types of macromolecules that are essential for all known forms of life. The two DNA strands are also known as polynucleotides as they are composed of simpler monomeric units called nucleotides. Each nucleotide is composed
Silicotungstic acid Silicotungstic acid Silicotungstic acid (also known as tungstosilicic acid) is the most commonly encountered heteropoly acid. It is a pale yellow solid with the chemical formula H[WSiO]. It is used as a catalyst in the chemical industry. Silicotungstic acid is used to manufacture ethyl acetate by the alkylation of acetic acid by ethylene: It has also been commercialized for the oxidation of ethylene to acetic acid: This route is claimed as a "greener" than methanol carbonylation. The heteropoly acid is dispersed on silica gel at 20-30 wt% to maximize catalytic ability. It has also recently been proposed as a mediator