Because these elements are most commonly bound to oxygen in the form of silicates, we may recalculate these elemental concentrations as oxides, assuming that all Si exists in as SiO2, Al as Al2O3, Fe is equally divided between FeO and Fe2O3 , Ca as CaO, Mg as MgO, Na as Na2O, K as K2O and Ti as TiO2. Use your periodic table to calculate weights. Calculate the molecular weight, wt.% element in a crust and wt.% oxide in a crust respectively.

Question

Because these elements are most commonly bound to oxygen in the form of silicates, we may recalculate these elemental concentrations as oxides, assuming that all Si exists in as SiO2, Al as Al2O3, Fe is equally divided between FeO and Fe2O3 , Ca as CaO, Mg as MgO, Na as Na2O, K as K2O and Ti as TiO2. Use your periodic table to calculate weights.  Calculate the molecular weight, wt.% element in a crust and wt.% oxide in a crust  respectively.

Bot GPT 3.5 · Answer

To calculate the molecular weight of each oxide, we need to use the atomic weight of each element from the periodic table: - SiO2 = 28.09 (Si) + 2 x 16.00 (O) = 60.09 g/mol - Al2O3 = 2 x 26.98 (Al) + 3 x 16.00 (O) = 101.96 g/mol - FeO = 55.85 (Fe) + 16.00 (O) = 71.85 g/mol - Fe2O3 = 2 x 55.85 (Fe) + 3 x 16.00 (O) = 159.69 g/mol - CaO = 40.08 (Ca) + 16.00 (O) = 56.08 g/mol - MgO = 24.31 (Mg) + 16.00 (O) = 40.31 g/mol - Na2O = 2 x 22.99 (Na) + 16.00 (O) = 61.98 g/mol - K2O = 2 x 39.10 (K) + 16.00 (O) = 94.20 g/mol - TiO2 = 47.87 (Ti) + 2 x 16.00 (O) = 79.87 g/mol Now we can calculate the wt.% of each element in a crust and the wt.% of each oxide in a crust.