Предмет: Химия, автор: зайка1999

массовая доля кремния в земной коре составляет 27,6 %, а кислорода - 49,1 %. Какое число атомов кремния приходится на каждые 1000 атомов в земной коре?

Ответы

Автор ответа: zerocool567

оставляешь пропорцию и получаешь х=(1000*0,276)/0,491=примерно 562 атома

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