TN1:

`Hh:Zn:x(mol);Fe:y(mol);Al:z(mol)`

`65x+56y+27z=20,4(1)`

`Zn+2HCl->ZnCl_2+H_2`

`Fe+2HCl->FeCl_2+H_2`

`2Al+6HCl->2AlCl_3+3H_2`

`n_{H_2}=x+y+1,5z={10,08}/{22,4}=0,45(2)`

TN2:

`Hh:Zn:kx(mol);Fe:ky(mol);Al:kz(mol)`

`k(x+y+z)=0,2(3)`

`Zn+Cl_2` $\xrightarrow{t^o}$ `ZnCl_2`

`2Fe+3Cl_2` $\xrightarrow{t^o}$ `2FeCl_3`

`2Al+3Cl_2` $\xrightarrow{t^o}$ `2AlCl_3`

`n_{Cl_2}=kx+1,5ky+1,5kz={6,16}/{22,4}=0,275(4)`

`(3)(4)->{x+y+z}/{x+1,5y+1,5z}=8/{11}`

`->3x-y-z=0(5)`

`(1)(2)(5)->x=0,1;y=0,2;z=0,1`

`m_{Zn}=0,1.65=6,5(g)`

`m_{Fe}=0,2.56=11,2(g)`

`m_{Al}=0,1.27=2,7(g)`

Bài 1:

Xét `20,4(g)hh:`

Đặt `n_{Zn} = a(mol); n_{Fe} = b(mol); n_{Al} = c(mol)`

`=> 65a + 56b + 27c = 20,4(1)`

`n_{H_2} = (10,08)/(22,4) = 0,45(mol)`

`Zn + 2HCl -> ZnCl_2 + H_2`

`a -> 2a -> a -> a`

`Fe + 2HCl-> FeCl_2 + H_2`

`b -> 2b -> b -> b`

`2Al + 6HCl -> 2AlCl_3 + 3H_2`

`c -> 3c -> c -> 1,5c`

`=> a + b + 1,5c = 0,45(2)`

Xét `0,2(mol) hh:`

`n_{Zn} = ak(mol); n_{Fe} = bk(mol); n_{Al} = ck(mol)`

`=> ak + bk + ck = 0,2(3)`

`n_{Cl_2} = (6,16)/(22,4) =0,275(mol)`

$Zn + Cl_2 \xrightarrow{t^o} ZnCl_2$

`ak -> ak`

$2Fe + 3Cl_2 \xrightarrow{t^o} 2FeCl_3$

`bk -> 1,5bk`

$2Al + 3Cl_2 \xrightarrow{t^o} 2AlCl_3$`

`ck -> 1,5ck`

`=> ak + 1,5bk + 1,5ck = 0,275(4)`

`(1),(2),(3),(4) => a = 0,1; b = 0,2; c =0,1; k = 1/2`

`m_{Zn} = 0,1.65 = 6,5(g)`

`m_{Fe} = 0,2.56 = 11,2(g)`

`m_{Al} = 0,1.27 = 2,7(g)`