From Wikipedia, the free encyclopedia. The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2.It is found in nature in several forms, including quartz and opal. In fact, silica has 17 crystalline forms.he chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2.
Windsor is home to 217,188 people, according to the 2016 census. Windsor's population has grown by three per cent in the past five years, but the city still fell behind the national growth rate, according to data collected during the 2016 census.
Windsor is a suburban town and tourist destination in the Royal Borough of Windsor and Maidenhead in Berkshire, England. It is best known as the site of Windsor Castle.The town is situated 21 miles (34 km) west of Charing Cross.It is immediately south of the River Thames, which forms its boundary with Eton.indsor Castle, in Windsor in the English county of Berkshire, is the largest inhabited castle in the world and, dating back to the time of William the Conqueror, is the oldest in continuous occupation.