Green green food colorings which has been approved by the US Food and Drug Administration. Chlorophyll, the E numbers E140 and E141, is the most common green chemical found in nature, and only allowed in certain medicines and cosmetic materials. Quinoline Yellow (E104) is a commonly used coloring in the United Kingdom but is banned in Australia, Japan, Norway and the United States. Green S (E142) is prohibited in many countries, for it is known to cause hyperactivity, asthma, urticaria, and insomnia. To create green sparks, fireworks use barium salts, such as barium chlorate, barium nitrate crystals, or barium chloride, also
Barium perchlorate Barium perchlorate Barium perchlorate is a powerful oxidizing agent, with the formula Ba(ClO). It is used in the pyrotechnic industry. Barium perchlorate decomposes at 505 °C. Gallucci and Gerkin (1988) analyzed the structure of the hydrate isomer Barium Perclorate Trihydrate (Ba(ClO)•3HO) by X-ray crystallography. The barium ions are coordinated by six water oxygen atoms at 2.919Å and six perchlorate oxygens at 3.026Å in a distorted icosahedral arrangement. The perchlorate fails by a narrow margin to have regular tetrahedral geometry, and has an average Cl-O bond length of 1.433Å. The space-group assignment of the structure was resolved, with the centrosymmetric assignment