pure+silica
71iron processing — Introduction use of a smelting process to turn the ore into a form from which products can be fashioned. Included in this article also is a discussion of the mining of iron and of its preparation for smelting. Iron (Fe) is a… …
72Germanium — (pronEng|dʒɚˈmeɪniəm) is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, silver white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Germanium has five naturally… …
73Precious Stones in the Bible — Precious Stones in the Bible † Catholic Encyclopedia ► Precious Stones in the Bible Precious stones are stones remarkable for their colour, brilliancy, or rarity. Such stones have at all times been held in high esteem everywhere,… …
74Chalcedony — A cut and polished Chalcedony geode General Category Oxide mineral Chemical formula …
75quartzite — quartzitic /kwawrt sit ik/, adj. /kwawrt suyt/, n. a granular metamorphic rock consisting essentially of quartz in interlocking grains. [1840 50; QUARTZ + ITE1] * * * Sandstone that has been converted into a solid quartz rock. Quartzites are… …
76Carbon dioxide — Carbon dioxide …
77Properties of water — H2O and HOH redirect here. For other uses, see H2O (disambiguation) and HOH (disambiguation). This article is about the physical and chemical properties of pure water. For general discussion and its distribution and importance in life, see Water …
78Chromatography — Pictured is a sophisticated gas chromatography system. This instrument records concentrations of acrylonitrile in the air at various points throughout the chemical laboratory. Chromatography (from Greek χρῶμα chroma color and γράφειν graphein to… …
79petroleum refining — Introduction conversion of crude oil into useful products. History Distillation of kerosene and naphtha The refining of crude petroleum owes its origin to the successful drilling of the first oil well in Titusville, Pa., in 1859. Prior to… …
80algae — algal, adj. /al jee/, n.pl., sing. alga / geuh/. any of numerous groups of chlorophyll containing, mainly aquatic eukaryotic organisms ranging from microscopic single celled forms to multicellular forms 100 ft. (30 m) or more long, distinguished… …
