Characteristics: Silver-white, ductile solid (beta-form). Changes to brittle grey (alpha) tin at temperatures below 18°C but the transition is normally very slow. Soluble in acids, and hot potassium hydroxide solution. Insoluble in water. Elemental tin has low toxicity, but most of it’s compounds are toxic.
Tin resists distilled sea and soft tap water, but is attacked by strong acids, alkalis, and acid salts. Oxygen in solution accelerates the attack. When heated in air, tin forms Sn2, which is feebly acid, forming stannate salts with basic oxides. The most important salt is the chloride, which is used as a reducing agent and as a mordant in calico printing. Tin salts sprayed onto glass are used to produce electrically conductive coatings. These have been used for panel lighting and for frost-free windshields. Most window glass is now made by floating molten glass on molten tin (float glass) to produce a flat surface (Pilkington process).
Hazards: All organic tin compounds are toxic. Tolerance, 2 mg/m3 of air; (organic compounds, as Sn), 0.1 mg/m3 of air.
There is an interesting phenomenon associated with tin called 'Tin Cry'. As a tin rod is bent the crystals re-align/shear and in the process emit a crackling sound. Want to hear tin cry?