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 bromide and can cause severe poisoning if ingested. Barium bromide Barium bromide is the chemical compound with the formula BaBr. Like barium chloride, it dissolves well in water and is toxic in aqueous solution. BaBr crystallizes in a lead chloride motif, giving white orthorhombic crystals which are deliquescent. In aqueous solution BaBr behaves as a simple salt. Barium bromide reacts with the sulfate ion from sulfuric acid to produce a precipitate of barium sulfate. Similar reactions occur with oxalic acid, hydrofluoric acid, and phosphoric acid. Barium bromide can be prepared from barium sulfide or barium carbonate via reaction with hydrobromic acid