Identify the reaction type shown and describe the clues that were used to identify it. Fe2O3 + 2SiO2 → Fe2Si2O7

Name the element in group 17, period 2. (periodic table)

How many grams of aluminum will there be in 98g of al2o3?

Large helium-filled balloons are used to lift scientific equipment to high altitudes. what is the pressure inside such a balloon if it starts out at sea level with a temperature of 10.0ºc and rises to an altitude where its volume is twenty times the original volume and its temperature is – 50.0ºc ?