vì B>A=>Zn, CuSO\(_4\) hết , Fe dư
n\(_{CuSO_{\text{4}}}\)=1.0,1=0,1mol
PTPU:
Zn+CuSO\(_4\)->ZnSO\(_4\)+Cu
x.........x...........x.............x(mol)
Fe+CuSO\(_4\)->FeSO\(_{\text{4}}\)+Cu
a...........a..........a..........a(mol)
\(m_{Zn}+m_{Fe}=m_A\)
65x+56y=8,38(1)
n\(_{CuSO_4}\)=x+a=0,1mol(2)
mặt khác:
\(m_{Cu}+m_{Fe_{dư}}=m_B\)
(64x+64a)+56(y-a)=8,64
<=>64x+64a+56y-56a=8,64
<=>64x+56y+8a=8,64(3)
từ (1),(2) và(3):
x=0,06mol;y=0,08mol;a=0,04mol
n\(_{Zn}\)=0,06mol
m\(_{Zn}\)=0,06.65=3.9g
m\(_{Fe}\)=\(m_A-m_{Zn}\)=8,38-3,9=4,48g