Предмет: Химия, автор: annet754

Даю 20 баллов
Какая масса осадка выделится при взаимодействии хлорида 100 г хлорида кальция содержащего 10 % примисей с фосфатом натрия ​

Ответы

Автор ответа: nikolaygr
1

Відповідь:

3CaCI2+2Na3PO4=Ca3(PO4)2+6NaCI

m(CaCI2)=100*(100-10)/100=90

M(CaCI2)=111г/моль

M(Ca3(PO4)2=310г/моль

n(CaCI2)=90/111=0,81моль

n(CaCI2):n(Ca3(PO4)2)=3:1

n(Ca3(PO4)2)=0,81/2=0,27моль

m(Ca3(PO4)2)=0,27*310=83,7г

Пояснення:

annet754: 0.81:2=0.405, а не 0.27
nikolaygr: там нужно делить 0,81 на три
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