Предмет: Химия, автор: maksim17996

1. Обчислити масові частки Оксигену в речовинах, формули яких К2О, NO2, FeSO4, Na2CO3. даю 20балов​

Ответы

Автор ответа: oficiant
2

K2O : K2 , O

w(O)= 16/39×2+16 ×100%= 17%

NO2 : N ,O2

w(O2)= 32/14+16×2×100%= 70%

FeSo4 : Fe,S,O4

w(O4)= 64/56+32+64= 64/152×100%= 42%

Na2Co3 : Na,C,O3

w(O3)= 48/23×2+12+16×3 ×100%= 45,2%

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