1) m(H2O)=120*1=120г; W(ZnCl2)=30/150=0,2(20%).
2)m(р-ра)=1000*1,12=1120г;
150г р-ра - 30г (ZnCl2)
1120г р-ра - xг (ZnCl2)
x=224г; n(ZnCl2)=224/136=1,65моль; Cм=1,65моль/л.
3)Сн=1,65:2=0,825моль/л
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