Ответ:
Объяснение:
Mr(Al2(SiO3)3) =27*2 + 28*3 + 16*9 =282
W(Al) = Ar(Al) *n / Mr(Al2(SiO3)3) *100% = 27*2 / 282 *100% =19%
W(Si) = Ar(Si) *n / Mr(Al2(SiO3)3) *100% = 28*3 / 282 *100% = 30%
W(O) = Ar(O) *n / Mr(Al2(SiO3)3) *100% = 16*9 / 282 *100% =51%