Предмет: Химия, автор: faer16228

1) рассчитать массовые доли химических элементов в Са(ОН)2 2) Выведите формулу вещества, содержащего 56% кальция и 44% серы.

Ответы

Автор ответа: Enimelia

1. m (Ca(OH)2)=40+2×(16+1)=74

w(Ca)=40/74×100%=54%

w(O)=32/74×100%=43,3%

w(H)=2/74×100%=2,7%

2. CaS

Проверка:

m(CaS)=40+32=72

w(Ca)=40/72×100%=55,6% ~ 56%

w(S)=32/72×100%=44,4% ~ 44%

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