Предмет: Химия, автор: Milla2000

определить массовую долю элементов в соединениях Al2(SO4)3

Ответы

Автор ответа: onegin60

Mr=Ar(Al)*2+Ar(S)*3+Ar(O)*12=27*2+32*3+16*12=54+96+192=342
w(Al)=Ar(Al)*2/Mr*100%=54/342*100%=16%
Аналогично, w(S)=28%
w(O)=56%

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