Carbon dioxide in Earth's atmosphere initial carbon dioxide in the atmosphere of the young Earth was produced by volcanic activity, modern volcanic activity releases only 130 to 230 megatonnes of carbon dioxide each year. These natural sources are nearly balanced by natural sinks, physical and biological processes which remove carbon dioxide from the atmosphere. For example, some is directly removed from the atmosphere by land plants for photosynthesis and it is soluble in water forming carbonic acid. There is a large natural flux of into and out of the biosphere and oceans. In the pre-industrial era these fluxes were largely in balance. Currently about 57%
Carbon dioxide US and Australia and New Zealand (listed by its INS number 290). A candy called Pop Rocks is pressurized with carbon dioxide gas at about 4 x 10 Pa (40 bar, 580 psi). When placed in the mouth, it dissolves (just like other hard candy) and releases the gas bubbles with an audible pop. Leavening agents cause dough to rise by producing carbon dioxide. Baker's yeast produces carbon dioxide by fermentation of sugars within the dough, while chemical leaveners such as baking powder and baking soda release carbon dioxide when heated or if exposed to acids. Carbon dioxide is used