Toxic solid

Phosphorus exists as white and red phosphorus. The former allotrope may be preserved in the dark at low temperatures but otherwise reverts to the more stable red form. The white form is a waxy, translucent, crystalline, highly-toxic solid subliming at room temperature and inflaming in air at 35°C, so it is handled under water. The red form is a reddish violet crystalline solid which vaporizes if heated at atmospheric pressure and condenses to give white phosphorus. The red form ignites in air at 260°C. Both are insoluble in water, and white phosphorus can be stored beneath it. Phosphorus forms a host of compounds such as phosphine, tri- and penta-halides, tri-, tetra- and penta-oxides, oxyacids including hypophosphorous, orthophosphorous and orthophosphoric acids. 

Liquid spillages may be sucked up by pump and non-toxic solids can be vacuumed or brushed up (after wetting down where appropriate). Only small quantities of inert, water-soluble waste should be discarded to drains acids and alkalis should first be neutralized. 

Solid waste can be burnt in suitable incinerators or disposed by burial at licensed land-fill sites. As for liquid wastes, the dumping of toxic solid waste at sea is now not acceptable. 

This volatile, toxic solid, mp 25.5°C, has a characteristic ozone-like odor. It is obtained when aqueous solutions of RuCl3(aq) are oxidized, e.g., by KI04, and... 

With solid electrodes (e.g. platinum), positive potentials of about +1.5 V can be reached but on the negative side, the hydrogen overvoltage is low and is a function of the electrode material and the pH of the solution. Moreover, solid electrodes often exhibit serious drawbacks as regards the background current which can be affected by the formation and/or removal of surface compounds, e.g., oxides. Nevertheless, in biological media only the non-toxic solid electrodes may be used. 

The uniqueness of the ferritin structure arises from the metabolic requirement to organize and utilize dissolved iron at concentrations and pH levels that induce precipitation of potentially toxic solid phases. Not only is iron solubilized by micelle encapsulation, but homeostatic control is also maintained. The study of ferritin therefore provides an important example of biological control of solid state reactions that involve the formation and organization of nanometer-size inorganic solids in biological time and space. 

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