\(n_{Fe}=0,2mol\)

\(Fe_xO_y+yH_2\rightarrow xFe+yH_2O\)

\(\dfrac{0,2}{x}\)..........................0,2

\(M_{Fe_xO_y}=\dfrac{16}{\dfrac{0,2}{x}}=80x\Leftrightarrow56x+16y=80x\Leftrightarrow\dfrac{x}{y}=\dfrac{2}{3}\)

\(\Rightarrow x=2;y=3\)

Oxit sắt là: \(Fe_2O_3\)

Đặt CTHH: Fe_xO_y

\(Fe_xO_y+yH_2\underrightarrow{t^o}xFe+yH_2O\)

\(n_{Fe}=\dfrac{11,2}{56}=0,2\left(mol\right)\)

\(n_{Fe_xO_y}=\dfrac{0,2}{x}\left(mol\right)\)

\(M_{Fe_xO_y}=\dfrac{16}{\dfrac{0,2}{x}}=80x\)

\(56x+16y=80x\)

\(\Leftrightarrow16y=24x\)

\(\Leftrightarrow\)\(\dfrac{x}{y}=\dfrac{16}{24}=\dfrac{2}{3}\)

\(\Rightarrow x=2;y=3\)

CTHH của oxit sắt: Fe₂O₃

a. \(Fe_2O_x+xH_2\rightarrow2Fe+xH_2O\)
b. \(n_{Fe}=\dfrac{m}{M}=\dfrac{1,05}{56}=0,01875\left(mol\right)\)

\(Fe_2O_x+xH_2\rightarrow2Fe+xH_2O\)

    1         :                2

 0,009375 :          0,01875

\(\Rightarrow M_{Fe_2O_x}=\dfrac{m}{n}=\dfrac{1,5}{0,009375}=160\) (g/mol)

\(\Rightarrow56.2+16x=160\)

\(\Rightarrow x=\dfrac{160-56.2}{16}=3\)

-Vậy CTHH của oxit sắt là Fe₂O₃

video là khí gì bạn =) 

a. \(Fe_xO_y+yH_2\rightarrow xFe+yH_2O\)

b. \(n_{Fe}=\dfrac{m}{M}=\dfrac{1,05}{56}=0,01875\)

\(Fe_xO_y+yH_2\rightarrow xFe+yH_2O\)

  1            :             x

\(\dfrac{0,01875}{x}\)  :          0,01875

\(\Rightarrow M_{Fe_xO_y}=\dfrac{m}{n}=\dfrac{1,5}{\dfrac{0,01875}{x}}=80x\)

\(\Rightarrow56x+16y=80x\)

\(\Rightarrow16y=24x\)

\(\Rightarrow\dfrac{x}{y}=\dfrac{16}{24}=\dfrac{2}{3}\)

\(\Rightarrow x=2;y=3\)

-Vậy CTHH của oxit sắt là Fe₂O₃

b

B

\(CT:Fe_xO_y\)

\(Fe_xO_y+yH_2\underrightarrow{^{t^o}}xFe+yH_2O\left(1\right)\)

\(Fe+2HCl\rightarrow FeCl_2+H_2\left(2\right)\)

\(n_{Fe}=n_{H_2\left(2\right)}=\dfrac{4.032}{22.4}=0.18\left(mol\right)\)

\(n_{H_2\left(1\right)}=\dfrac{y}{x}\cdot n_{Fe}=\dfrac{5.376}{22.4}=0.24\left(mol\right)\)

\(\Leftrightarrow\dfrac{y}{x}\cdot0.18=0.24\)

\(\Leftrightarrow\dfrac{x}{y}=\dfrac{3}{4}\)

\(CT:Fe_3O_4\)

\(m_{Fe_3O_4}=\dfrac{0.18}{3}\cdot232=13.92\left(g\right)\)

Câu 1:

PTHH: \(Fe+2HCl\rightarrow FeCl_2+H_2\uparrow\)

Ta có: \(\left\{{}\begin{matrix}n_{Fe}=\dfrac{11,2}{56}=0,2\left(mol\right)\\n_{HCl}=\dfrac{43,8}{36,5}=1,2\left(mol\right)\end{matrix}\right.\)

Xét tỉ lệ: \(\dfrac{0,2}{1}< \dfrac{1,2}{2}\) \(\Rightarrow\) HCl còn dư, Fe p/ứ hết

\(\Rightarrow n_{H_2}=0,2\left(mol\right)\) \(\Rightarrow V_{H_2}=0,2\cdot22,4=4,48\left(l\right)\) 

Câu 2:

PTHH: \(RO+H_2\underrightarrow{t^o}R+H_2O\)

Ta có: \(n_{RO}=n_{H_2}=\dfrac{11,2}{22,4}=0,5\left(mol\right)\)

\(\Rightarrow\dfrac{36}{M_R+16}=0,5\) \(\Rightarrow M_R=56\)  (Sắt)

  Vậy CTHH cần tìm là FeO