Предмет: Химия, автор: violeta7825

при сплавленні 19,6 г цинк гідроксиду з лугом, утвореним елементом і групи періодичної системи, одержали 35 г цинкату цього елемента. установіть формулу лугу. Допоможіть будь ласка !!!

Ответы

Автор ответа: unezhewaoxnw6u

3

Объяснение:

2XOH + Zn(OH)2 = X2ZnO2 + 2H2O.

Щёлочь имеет формулу ХОН

Молярная масса Zn(OH)2 99г/моль

Молярная масса неизвестного цинката 2х+97 г/моль

n(Zn(OH)2)=n(X2ZnO2)

19.6/99=35/(2x+97)

0.2=35/(2x+97)

35=0.2•(2x+97)

35=0.4x+19.4

0.4x=15.6

x=39 это Калий

2КOH + Zn(OH)2 = К2ZnO2 + 2H2O.

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Mayflower
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