Pengguna:Agung.karjono/Bak pasir/Timbal(II) nitrat: Perbedaan antara revisi

▲ The [[point group]] of cyclo-S₈ is D_4d and its dipole moment is 0 D. Octasulfur is a soft, bright-yellow solid that is odorless, but impure samples have an odor similar to that of [[match]]es.<ref>A strong odor called "smell of sulfur" actually is given off by several sulfur compounds, such as [[hydrogen sulfide]] and [[organosulfur]] compounds.</ref> It melts at {{convert|115.21|C}}, boils at {{convert|444.6|C}} and sublimes easily.<ref name="Greenwd" /> At {{convert|95.2|C}}, below its melting temperature, cyclo-octasulfur changes from α-octasulfur to the β-[[polymorphism (materials science)|polymorph]].<ref name="Greenwood">{{Greenwood&Earnshaw2nd|pages= 645–665}}</ref> The structure of the S₈ ring is virtually unchanged by this phase change, which affects the intermolecular interactions. Between its melting and boiling temperatures, octasulfur changes its allotrope again, turning from β-octasulfur to γ-sulfur, again accompanied by a lower density but increased [[viscosity]] due to the formation of [[polymer]]s.<ref name="Greenwood" /> At higher temperatures, the viscosity decreases as depolymerization occurs. Molten sulfur assumes a dark red color above {{convert|200|C}}. The density of sulfur is about 2&nbsp;g/cm³, depending on the allotrope; all of the stable allotropes are excellent electrical insulators.