41. The metal is extracted from the solution as oxalate and converted to oxide by heating. 42. Because of this, some urologists recommend chewing calcium tablets during meals containing oxalate foods. 43. By adding a reagent, here ammonia, the calcium will precipitate as calcium oxalate . 44. Upon treatment with concentrated sulphuric acid, oxalates yield colourless CO 2 and CO gases. 45. The fruit contains high levels of oxalate . 46. Whewellite, or at least crystalline calcium oxalate , does also arise from biological sources. 47. More complex bridging ligands are also well known including oxalate , malonate, and pyrazine. 48. Plants like Tradescantia pallida also accumulate calcium oxalate crystals in response to heavy metals stress. 49. Oxalate products are also used because they reduce dentin permeability and occlude tubules more consistently.50. Hyperoxaluria refers to oxalate derived from dietary sources or that which is secondary to malabsorption.
