Предмет: Химия, автор: leksa101

ПОМОГИТЕ SOS !!!!!!!!!! ХИМИЯ
дам 100 баллов
решите задачи 4,5,6,7​

Приложения:

Ответы

Автор ответа: ivanmal91
1

Объяснение:

1 задача

m(NaCl)=m(раствора)*w(NaCl)/100=200*15/100=30 г

w(NaCl) '=m(NaCl)/m(раствора)'=100*30/(200+200)=7.5 %

2 задача

w(Au)=100-w(Cu)=58.5 %

m(Au)=2.8*58.5/100=1.638 г

3 задача

Запишем уравнение реакции разложения карбоната кальция

CaCO3=CaO+CO2

n(CaCO3)=12/100=0.12 моль

n(CaO)=n(CaCO3)=0.12 моль

m(CaO)=n*M=6.72 г

N=100*m(CaO)пр/m(CaO)теор=100*6/6.72=89.3 %

4 задача

n(KOH)=m/M=120/56=2.143 моль

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