Предмет: Химия, автор: curkanmaksim299

дорогоціний камінь рубін і сапфір містять цю речовину це сполука складається з двох елементів алюміі і оксигену у 51г речовини містить 27г алюмінію знайди масову частину оксигену

Ответы

Автор ответа: wdfkef

Ответ: 1)массовая доля кальция=40:234=0,17(17%)

массовая доля фосфора=62:234-0,26(26%)

массовая доля кислорода=128:234=0,55(55%)

2)массовая доля кислорода=24:51-0,47(47%)

3) СН4

12:4

3:1

4:1=Х:2

Х=8(кг)метана

Объяснение: у меня 12 по химии :)

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