\(n_{Na}=\dfrac{4.6}{23}=0.2\left(mol\right)\)
\(n_{NaOH}=0.2\left(mol\right)\)
\(n_{FeCl_3}=0.1\cdot1=0.1\left(mol\right)\)
\(Na+H_2O\rightarrow NaOH+\dfrac{1}{2}H_2\)
\(3NaOH+FeCl_3\rightarrow3NaCl+Fe\left(OH\right)_3\)
\(3....................1\)
\(0.2.............0.1\)
\(LTL:\dfrac{0.2}{3}< \dfrac{0.1}{1}\Rightarrow FeCl_3dư\)
\(m_{Fe\left(OH\right)_3}=\dfrac{0.2}{3}\cdot107=7.13\left(g\right)\)
\(Na+H_2O\rightarrow NaOH+\dfrac{1}{2}H_2\)
\(3NaOH+FeCl_3\rightarrow Fe\left(OH\right)_3+3NaCl\)
\(n_{Na}=n_{NaOH}=\dfrac{4,6}{23}=0,2\left(mol\right)\)
\(n_{Fe\left(OH\right)_3}=0,1.1=0,1\left(mol\right)\)
Lập tỉ lệ : \(\dfrac{0,2}{3}< \dfrac{0,1}{1}\) => FeCl3 dư, NaOH hết
\(n_{Fe\left(OH\right)_3}=\dfrac{1}{3}n_{NaOH}=\dfrac{0,2}{3}=\dfrac{1}{15}\left(mol\right)\)
=> \(m_{Fe\left(OH\right)_3}=\dfrac{1}{15}.107=7,13\left(g\right)\)