Предмет: Химия, автор: киса302

Помогите пожалуйста с С1, С2 спассииииииибо)

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Ответы

Автор ответа: Himik1991

1) 200/100*21=42

2)Na2CO3 (Карбонат натрия) M(Na2CO3)=23*2+12+16*3=106
Na=46/106*100=43.4%

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