Предмет: Химия, автор: Absolute4567

1. Обчислити відносну молекулярну масу речовин PbO , BaSO4.
2. Знайти співвідношення мас атомів у молекулі KNO3.
3. Обчислити масові частки елементів у складних речовинах: CH4, Al4C

Ответы

Автор ответа: polinakozur850

1.PbO 207 + 16 = 223

KCl 39 + 35 =74

BaSO4 137 + 32 + 64 = 233

3.1)Mr(CH4)=12+1*4=16

W(C)=12/16*100%=75%

W(H)=4/16*100%=25%

Absolute4567: А як друге робити

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