a) \(Cu+S\underrightarrow{t^o}CuS\)
b) \(n_{Cu}=\frac{6,4}{64}=0,1\left(mol\right)\); \(n_S=\frac{9,6}{32}=0,3\left(mol\right)\)
Xét tỉ lệ: \(\frac{0,1}{1}< \frac{0,3}{1}\) => Cu hết, S dư
PTHH: \(Cu+S\underrightarrow{t^o}CuS\)
______0,1-->0,1-->0,1_____(mol)
=> \(n_{CuS}=0,1\left(mol\right)\)
c) \(\left\{{}\begin{matrix}m_{CuS}=0,1.96=9,6\left(g\right)\\m_S=\left(0,3-0,1\right).32=6,4\left(g\right)\end{matrix}\right.\)