Answer :
n=m/M
n(Cu2S)=5/(63.55*2+32.06)=5/159.16=0.0314149
n(cu)=n(cu2s)*2=0.0628298
m(cu)=0.0628298*63.55=3.99
Answer 3.99 gram cu
n(Cu2S)=5/(63.55*2+32.06)=5/159.16=0.0314149
n(cu)=n(cu2s)*2=0.0628298
m(cu)=0.0628298*63.55=3.99
Answer 3.99 gram cu