СuСО3(ОН)2
найдем относительную молекулярную массу вещества:
Mr=64+12+48+32+2=158
w(Cu) = 64/158 =0,405 = 40,5%
PbS
Mr=207+32 = 239
w(Pb)=207/239 = 0,866 = 86,6%
Fe2O3
Mr =112 + 48 = 160
w(Fe) = 112/160 = 0,7 = 70%
NiS
Mr=58+32 = 90
w(Ni)= 58/90 =0,644= 64,4%
Cu2S
Mr= 128+32 = 160
w(Cu) = 128/160=0,8=80%
Cu2O
Mr= 128+16 = 144
w(Cu)=128/144 0,889 = 88,9%