Chelate
A chelate is a compound in which a metal ion is held by an organic molecule. Certain chelated nutrient products help keep elements such as iron available under conditions where they would otherwise become less soluble. The chelating agent and soil pH matter, so products are not interchangeable simply because their labels say chelated. For a mango with suspected nutrient deficiency, consider root health and test information first; a chelate does not correct flooding, damaged roots, or every cause of yellow foliage.