a)
\(n_{Cl_2} = \dfrac{6,72}{22,4}\ =0,3(mol)\)
mmuối= mkim loại + mCl2 = 8,3 + 0,3.71 = 29,6(gam)
b)
\(\left\{{}\begin{matrix}Al:x\left(mol\right)\\Fe:y\left(mol\right)\end{matrix}\right.\)⇒27x + 56y = 8,3(1)
\(2Al + 3Cl_2 \xrightarrow{t^o} 2AlCl_3\\ 2Fe + 3Cl_2 \xrightarrow{t^o} 2FeCl_3\)
Suy ra : 1,5x + 1,5y = 0,3(2)
Từ (1)(2) suy ra : x = 0,1 ; y = 0,1
Vậy :
\(\%m_{Al} = \dfrac{0,1.27}{8,3}.100\% = 32,53\%\\ \%m_{Fe} = 100\% - 32,53\% = 67,47\%\)
\(Đặt:n_{Al}=x\left(mol\right),n_{Fe}=y\left(mol\right)\)
\(m_{hh}=27x+56y=8.3\left(g\right)\left(1\right)\)
\(n_{Cl_2}=0.3\left(mol\right)\)
\(2Al+3Cl_2\underrightarrow{t^0}2AlCl_3\)
\(2Fe+3Cl_2\underrightarrow{t^0}2FeCl_3\)
\(n_{Cl_2}=1.5x+1.5y=0.3\left(mol\right)\left(2\right)\)
\(\left(1\right),\left(2\right):x=y=0.1\)
\(m_{Muối}=m_{AlCl_3}+m_{FeCl_3}=0.1\cdot133.5+0.1\cdot162.5=29.6\left(g\right)\)
\(\%Al=\dfrac{2.7}{8.3}\cdot100\%=32.53\%\)
\(\%Fe=100-32.53=67.47\%\)