Предмет: Химия, автор: khrustalyova1

Масова частка деякого елемента головної підгрупи ||| групи в його вищому оксиді становить - 52,9%. Назвіть цей елемент, напишіть формулу цього оксиду і напишіть електронну формулу його атома

Ответы

Автор ответа: dyexfnf
2

Ответ:

Объяснение:

Формула вищого оксиду ||| групи R₂О₃.

Знайдемо масову частку Оксигену:

w(O) = 100% - w(R) = 100% - 52,9% = 47,1%

В оксиді 3 атоми Оксигену і молекулярна маса його складає:

М(О₃) = 16 * 3 = 48 г/моль

48 г/моль  - 47,1%

М(R₂О₃) г/моль - 100%

М(R₂О₃) = 48 * 100% : 47,1 % = 102 г/моль молекулярна маса сполуки

R₂ = М(R₂О₃) - М(О₃) = 102 - 48 = 54 г/моль

Знайдемо елемент головної підгрупи ||| групи

R = R₂ /2 = 54 /2 = 27 г/моль

Отже цей елемент Алюміній

Формула оксиду: Al₂О₃

Електронна формула алюмінію — 1s²2s²2p⁶3s²3p¹

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