giúp e câu này với ạ

Đặt `n_{MgCl_2}=x(mol);n_{FeCl_3}=y(mol);n_{CuCl_2}=z(mol)`

TN1:

`CuCl_2+H_2S->CuS+2HCl`

`2FeCl_3+H_2S->2FeCl_2+2HCl+S`

Theo PT: `n_{CuS}=z(mol);n_S=0,5y(mol)`

`->0,5y.32+96z=16(1)`

TN2:

`MgCl_2+Na_2S+2H_2O->Mg(OH)_2+H_2S+2NaCl`

`2FeCl_3+3Na_2S->2FeS+S+6NaCl`

`CuCl_2+Na_2S->CuS+2NaCl`

Theo PT:

`->58x+88y+0,5y.32+96z=30,6(2)`

TN3

`MgCl_2+Na_2S+2H_2O->Mg(OH)_2+H_2S+2NaCl`

`FeCl_2+Na_2S->FeS+2NaCl`

`CuCl_2+Na_2S->CuS+2NaCl`

Theo PT: `n_{Mg(OH)_2}=x(mol);n_{FeS}=y(mol);n_{CuS}=z(mol)`

`->58x+88y+96z=29(3)`

`(1)(2)(3)->x=0,1(mol);y=0,1(mol);z=0,15(mol)`

`m_{MgCl_2}=0,1.95=9,5(g)`

`m_{FeCl_3}=0,1.162,5=16,25(g)`

`m_{CuCl_2}=0,15.135=20,25(g)`