произвести вычисление по формуле al2o3

Al2O3

W(Al) = Ar(Al) *n / Mr(Al2O3) * 100% = 27 * 2 / 102 *100% =52,94 %

W(O) = Ar(O) * n / Mr(Al2O3) *100% = 16 *3 / 102 *100% = 47,05%

Mr(Al2O3) = 27*2 + 16*3 = 102