a, Theo gt ta có: \(n_{FeO}=\dfrac{10}{72}=\dfrac{5}{36}\left(mol\right)\)
PTHH: \(FeO+2HCl\rightarrow FeCl_2+H_2O\) (1)
Theo (1);gt: \(\dfrac{5}{36}....\dfrac{5}{18}.....\dfrac{5}{36}....\dfrac{5}{36}\left(mol\right)\)
\(\Rightarrow m_{HCl}=\dfrac{5}{18}.36,5=\dfrac{365}{36}\left(g\right)\\ \Rightarrow\%C_{HCl}=\dfrac{\dfrac{365}{36}.100\%}{100}\approx10,14\%\)
b, Theo pt (*) ta có: \(m_{H_2O}=\dfrac{5}{36}.18=2,5\left(g\right);m_{FeCl_2}=\dfrac{5}{36}.127=\dfrac{635}{36}\left(g\right)\)
Áp dụng định luật bảo toàn khối lượng cho pt (*); gt và dung dịch ta có:
\(m_{FeCl_2}=m_{FeO}+m_{FeCl_2}+m_{H_2O}=10+100+2,5=112,5\left(g\right)\)
\(\Rightarrow\%C_{FeCl_2}=\dfrac{\dfrac{635}{36}.100\%0}{112,5}\approx15,68\%\)
\(\)
