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

PTHH: Fe + 2HCl --> FeCl₂ + H₂

          0,2------------>0,2----->0,2

=> \(\left\{{}\begin{matrix}m_{FeCl_2}=0,2.127=25,4\left(g\right)\\V_{H_2}=0,2.22,4=4,48\left(l\right)\end{matrix}\right.\)

Bài 1 : 

\(a) Fe_2O_3 + 3H_2 \xrightarrow{t^o}2Fe + 3H_2O\\ b) n_{Fe_2O_3} = \dfrac{80}{160}= 0,5(mol)\\ n_{H_2} = 3n_{Fe_2O_3} = 1,5(mol)\\ \Rightarrow V_{H_2} = 1,5.22,4 = 33,6(lít)\\ n_{Fe} = 2n_{Fe_2O_3} = 1(mol)\\ m_{Fe} = 1.56 = 56(gam)\)

Bài 2 :

\(a) Fe + 2HCl \to FeCl_2 + H_2\\ n_{H_2} = n_{Fe} =\dfrac{5,6}{56} = 0,1(mol)\\ V_{H_2} = 0,1.22,4 = 2,24(lít)\\ n_{HCl} =2 n_{Fe} = 0,2(mol)\\ m_{HCl} = 0,2.36,5 = 7,3(gam)\)

mHCl= 3,65%.400= 14,6(g) => nHCl=14,6/36,5=0,4(mol)

a) PTHH: Mg +2 HCl -> MgCl2 + H2

0,2__________0,4_____0,2____0,2(mol)

V(H2,đktc)=0,2.22,4=4,48(l)

b)mMg=0,2.24=4,8(g)

c) mMgCl2= 0,2.95=19(g)

mddMgCl2= 400+4,8 - 0,2.2= 404,4(g)

=> C%ddMgCl2= (19/404,4).100=4,698%

a, \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

\(n_{HCl}=0,15.4=0,6\left(mol\right)\)

Theo PT: \(n_{H_2}=\dfrac{1}{2}n_{HCl}=0,3\left(mol\right)\Rightarrow V_{H_2}=0,3.22,4=6,72\left(l\right)\)

b, \(n_{Zn}=\dfrac{1}{2}n_{HCl}=0,3\left(mol\right)\Rightarrow m_{Zn}=0,3.65=19,5\left(g\right)\)

c, \(n_{ZnCl_2}=\dfrac{1}{2}n_{HCl}=0,3\left(mol\right)\Rightarrow C_{M_{ZnCl_2}}=\dfrac{0,3}{0,15}=2\left(M\right)\)

PT: \(Fe+2HCl\rightarrow FeCl_2+H_2\)

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

Theo PT: \(\left\{{}\begin{matrix}n_{H_2}=n_{FeCl_2}=n_{Fe}=0,2\left(mol\right)\\n_{HCl}=2n_{Fe}=0,4\left(mol\right)\end{matrix}\right.\)

a, Ta có: \(V_{H_2}=0,2.22,4=4,48\left(l\right)\)

b, \(V_{ddHCl}=\dfrac{0,4}{1,5}\approx0,267\left(l\right)\)

c, \(m_{FeCl_2}=0,2.127=25,4\left(g\right)\)

Bạn tham khảo nhé!

Bài 3:

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

$Fe+2HCl\to FeCl_2+H_2\uparrow$

Theo PT: $n_{FeCl_2}=n_{H_2}=0,2(mol)$

$\Rightarrow m_{FeCl_2}=0,2.127=25,4(g);V_{H_2}=0,2.22,4=4,48(lít)$

$\Rightarrow m=25,4;V=4,48$

Bài 4:

$CuO+H_2SO_4\to CuSO_4+H_2O$

Theo PT; $n_{H_2SO_4}=n_{CuSO_4}=n_{CuO}=\dfrac{32}{80}=0,4(mol)$

$\Rightarrow m_{H_2SO_4}=0,4.98=39,2(g)$

$m_{CuSO_4}=0,4.160=64(g)$

\(a,Fe+2HCl\rightarrow FeCl_2+H_2\\ CuO+2HCl\rightarrow CuCl_2+H_2O\\ n_{H_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\Rightarrow n_{Fe}=n_{H_2}=0,1\left(mol\right)\\ \Rightarrow\%m_{Fe}=\dfrac{0,1.56}{13,6}.100\%\approx41,176\%\\ \Rightarrow\%m_{CuO}\approx58,824\%\\ b,n_{CuO}=\dfrac{13,6-0,1.56}{80}=0,1\left(mol\right)\\ n_{HCl\left(p.ứ\right)}=2.\left(n_{Fe}+n_{CuO}\right)=2.\left(0,1+0,1\right)=0,4\left(mol\right)\\ \Rightarrow V_{ddHCl}=\dfrac{0,4}{2}=0,2\left(l\right)\)

a , \(nFe=\dfrac{11,2}{56}=0,2\left(mol\right)\)

, pthh:

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

1mol   2mol       1mol      1mol

0,2     0,4              0,2       0,2

\(FeCl_2+2NaOH\rightarrow Fe\left(OH\right)_2\downarrow+2NaCl\)

1mol        2mol           1mol              2mol

0,2            0,4               0,2            0,4

b, \(mFe\left(OH\right)_2=0,2.90=18\left(gam\right)\)

a , 

a) Sửa đề: dd H₂SO₄ 9,8%

Ta có: \(n_{H_2}=\dfrac{7,84}{22,4}=0,35\left(mol\right)\) \(\Rightarrow m_{H_2}=0,35\cdot2=0,7\left(g\right)\)

Bảo toàn nguyên tố: \(n_{H_2SO_4}=n_{H_2}=0,35\left(mol\right)\) \(\Rightarrow m_{ddH_2SO_4}=\dfrac{0,35\cdot98}{9,8\%}=350\left(g\right)\)

\(\Rightarrow m_{dd}=m_{KL}+m_{H_2SO_4}-m_{H_2}=361,6\left(g\right)\)

b) Tương tự câu a