Cu+2H2SO4=CuSO4+SO2+2H2O
CuO+H2SO4=CuSO4+H2O
SO2+Br2+2H2O=2HBr+H2SO4
m(Br2)в-ва=mр-ра*ω/100%=1000*4%/100%=40г
n(Br2)=m/M=40г/160г/моль=0,25моль
n(Br2)=n(SO2)=n(Cu)=0.25моль
m(Cu)=n*M=0.25*54=16г
ω(Cu)=m(Cu)/mсмеси*100%=16/50*100%=32%
ω(СuO)=100%-ω(Cu)=100%-32%=68%