m(CuSO4,20%)=V*плотность=400*1,19=476г, m(CuSO4,100%)=m(CuSO4,20%)*w(CuSO4)/100%=476*20/100=95,2г, n(CuSO4)=m/M=95,2/160=0,595моль, n(CuSO4*5H2O)=m/M=50/250=0,2моль, n(CuSO4,остав)=n(CuSO4)-n(CuSO4*5H2O)=0,595-0,2=0,395моль, m(CuSO4,остав)=n*M=0,395*160=63,2г, m(р-ра)=m(CuSO4,20%)-m(CuSO4*5H2O)=400-50=350г, w(CuSO4,остав)=m(CuSO4,остав)*100%/m(р-ра)=63,2*100/350=18,06%. ответ: w(CuSO4,остав)=18,06%.
m(CuSO4,20%)=V*плотность=400*1,19=476г, m(CuSO4,100%)=m(CuSO4,20%)*w(CuSO4)/100%=476*20/100=95,2г, n(CuSO4)=m/M=95,2/160=0,595моль, n(CuSO4*5H2O)=m/M=50/250=0,2моль, n(CuSO4,остав)=n(CuSO4)-n(CuSO4*5H2O)=0,595-0,2=0,395моль, m(CuSO4,остав)=n*M=0,395*160=63,2г, m(р-ра)=m(CuSO4,20%)-m(CuSO4*5H2O)=400-50=350г, w(CuSO4,остав)=m(CuSO4,остав)*100%/m(р-ра)=63,2*100/350=18,06%. ответ: w(CuSO4,остав)=18,06%.