Предмет: Химия, автор: lavrenyukdasha

3. Обчисліть відносні молекулярні маси для таких речовин: а) Н2SO3; б) Mg(OH)2 .
4.Обчисліть масу солі та об’єм води, які необхідні для приготування 230г розчину з масовою часткою солі 15% .
5. До 160 г розчину з масовою часткою цукру 3% додали 40 г цукру. Обчисліть масову частку цукру в отриманому розчині.

Ответы

Автор ответа: yulialegoss

Ответ:

а)Мr(Н2SО3)=(1х2)+32+(16х3)=82

б)Мr(Мg[ОН]2)=24+(16+1)2=58

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