Pure sulfur exists in two stable crystalline forms (a) Alpha-sulfur: rhombic, octahedral yellow crystals stable at room temperature. (b) Beta-sulfur: monoclinic, prismatic pale yellow crystals slowly changing to alpha form below 94.5°C. Both forms are insoluble in water, but slightly soluble in alcohol and ether. Soluble in carbon disulfide, carbon tetracholoride, and benzene. Purity sulfur is Conbustible, nontoxic. Purity sulfur has fire and explosion risk in finely divided form.| Symbol: | S |
| Atomic Number: | 16 |
| Atomic Weight: | 32.06 |
| Density: | 2.07 gm/cc (rhombic) |
| Melting Point: | 112.8 oC (rhombic) |
| Boiling Point: | 444.674 oC |
| Thermal Conductivity: | 0.00205 W/cm/K @ 298.2 K |
| Electrical Resistivity: | 2x1023 microhm-cm @ 20 oC |
| Electronegativity: | 2.5 Paulings |
| Specific Heat: | 0.175 Cal/g/K @ 25 oC |
| Heat of Vaporization: | 3.01 K-cal/gm atm at 444.674 oC |
| Heat of Fusion: | 0.295 Cal/gm mole |
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