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silica
(Encyclopedia)silica or silicon dioxide, chemical compound, SiO2. It is insoluble in water, slightly soluble in alkalies, and soluble in dilute hydrofluoric acid. Pure silica is colorless to white. It occurs in sev...Taj Mahal
(Encyclopedia)Taj Mahal täzh məhälˈ, täj məhŭlˈ [key], mausoleum, Agra, Uttar Pradesh state, N India, on the Yamuna River. It is considered one of the most beautiful buildings in the world and the finest ex...National Parks and Monuments (table)
(Encyclopedia)National Parks and Monuments 1 National Parks and Monuments National Monuments National and International Historic Sites and Historical Parks National Memorials National Battlef...Browse by Subject
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