Предмет: Химия, автор: natasha398

Найпростішою формулою нітроген оксиду, у якому масова частка Нітрогену в 1,75 оаза більша за масову частку Оксигену, є: а) N2O5 б) NO в) NO2 г) N2O

Ответы

Автор ответа: bearcab

4

Молярная масса азота равна 14 г/моль, а молярная масса кислорода равна 16 г/моль. Следовательно, чтобы азота в веществе было больше, чем кислорода, нужно, чтобы атомов азота в формуле было больше, чем атомов кислорода. Сразу же отпадают варианты а), б), в). Остается проверить вариант г)

M(N)=2*14=28 г/моль

М(О)=16 г/моль.

28:16=1,75.

Значит ответ г) - закись азота (веселящий газ - наркотическое вещество, используется в медицине).

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