Bài 3 : 

\(n_{Al}=\dfrac{2,7}{27}=0,1\left(mol\right)\)

Pt : \(2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2|\)

        2            3                   1               3

       0,1       0,15                 0,05       0,15

a) \(n_{H2}=\dfrac{0,1.3}{2}=0,15\left(mol\right)\)

\(m_{H2}=0,15.2=0,3\left(g\right)\)

\(V_{H2\left(dktc\right)}=0,15.22,4=3,36\left(l\right)\)

b) \(n_{H2SO4}=\dfrac{0,1.3}{2}=0,15\left(mol\right)\)

⇒ \(m=0,15.98=14,7\left(g\right)\)

\(C_{ddH2SO4}=\dfrac{14,7.100}{200}=7,35\)⁰/₀

c) \(n_{Al2\left(SO4\right)3}=\dfrac{0,15.1}{3}=0,05\left(mol\right)\)

⇒ \(m_{Al2\left(SO4\right)3}=0,05.342=17,1\left(g\right)\)

\(m_{ddspu}=2,7+200-0,3=302,4\left(g\right)\)

\(C_{Al2\left(SO4\right)3}=\dfrac{17,1.100}{302,4}=5,65\)⁰/₀

 Chúc bạn học tốt

\(n_{Zn}=\dfrac{13}{65}=0.2\left(mol\right)\)

\(Zn+2HCl\rightarrow ZnCl_2+H_2\)

\(0.2.......0.4......................0.2\)

\(V_{H_2}=0.2\cdot22.4=4.48\left(l\right)\)

\(m_{HCl}=0.4\cdot36.5=14.6\left(g\right)\)

\(C\%_{HCl}=\dfrac{14.6}{146}\cdot100\%=10\%\)

a,\(n_{Al}=\dfrac{2,7}{27}=0,1\left(mol\right)\)

PTHH: 2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂

Mol:     0,1        0,15           0,05           0,15

\(m_{H_2}=0,15.2=0,3\left(g\right)\)

\(V_{H_2}=0,15.24,79=3,7185\left(l\right)\)

b, \(m_{ddH_2SO_4}=\dfrac{0,15.98.100\%}{200}=7,35\%\)

c, m_{dd sau pứ} = 2,7 + 200 - 0,3 = 202,4 (g)

\(C\%_{ddAl_2\left(SO_4\right)_3}=\dfrac{0,05.342.100\%}{202,4}=8,45\%\)

ai đi ngang giúp mk vs :((

ai đi ngang giúp a

a) 

\(n_{Zn}=\dfrac{16,25}{65}=0,25\left(mol\right)\)

PTHH: Zn + H₂SO₄ --> ZnSO₄ + H₂

         0,25-->0,25------------->0,25

=> V_H2 = 0,25.22,4 = 5,6 (l)

b) \(C_{M\left(dd.H_2SO_4\right)}=\dfrac{0,25}{0,3}=\dfrac{5}{6}M\)

c) \(n_{Fe_2O_3}=\dfrac{32}{160}=0,2\left(mol\right)\)

PTHH: Fe₂O₃ + 3H₂ --t^o--> 2Fe + 3H₂O

Xét tỉ lệ: \(\dfrac{0,2}{1}>\dfrac{0,25}{3}\) => Fe₂O₃ dư, H₂ hết

PTHH: Fe₂O₃ + 3H₂ --t^o--> 2Fe + 3H₂O

           \(\dfrac{0,25}{3}\) <--0,25----->\(\dfrac{0,5}{3}\)

=> \(m=32-\dfrac{0,25}{3}.160+\dfrac{0,5}{3}.56=28\left(g\right)\)

PTHH: \(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\)

đb:       0,25

a) số mol của Zn là: \(n_{Zn}=\dfrac{m_{Zn}}{M_{Zn}}=\dfrac{16,25}{65}=0,25\left(mol\right)\)

Theo PTHH, ta có: \(n_{H_2}=\dfrac{0,25\cdot1}{1}=0,25\left(mol\right)\)

Thể tích của H₂ ở đktc là: \(V_{H_2\left(đktc\right)}=n_{H_2}\cdot22,4=0,25\cdot22,4=5,6\left(l\right)\)

2 câu còn lại mk chịu

em không biết

\(n_{Zn}=\dfrac{26}{65}=0,4\left(mol\right)\\ pthh:Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\) 
           0,4       0,8        0,4           0,4
\(a,V_{H_2}=0,4.22,4=8,96\left(l\right)\\ b,C\%_{HCl}=\dfrac{0,8.36,5}{150}.100\%=19,5\%\\ c,m_{\text{dd}}=26+150-\left(0,4.2\right)=175,2\left(g\right)\\ C\%_{ZnCl_2}=\dfrac{0,4.136}{175,2}.100\%=31\%\)

\(n_{Zn}=\dfrac{13}{65}=0,2\left(mol\right)\)

PTHH: Zn + H₂SO₄ ---> ZnSO₄ + H₂

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

\(V_{H_2}=0,2.22,4=4,48\left(l\right)\\ m_{H_2SO_4}=\dfrac{0,2.98}{20\%}=98\left(g\right)\\ \rightarrow V_{ddH_2SO_4}=\dfrac{98}{1,14}=86\left(ml\right)=0,086\left(l\right)\\ \rightarrow C_{M\left(H_2SO_4\right)}=\dfrac{0,2}{0,086}=2,33M\)

Sửa:

`Zn + H_2 SO_4 -> ZnSO_4 + H_2`

`0,25`     `0,25`                             `0,25`      `(mol)`

`n_[Zn]=[16,25]/65=0,25(mol)`

`a)V_[H_2]=0,25.22,4=5,6(l)`

`b)C_[M_[H_2 SO_4]]=[0,25]/[0,3]~~0,8(M)`

`c)`

`3H_2 + Fe_2 O_3` $\xrightarrow{t^o}$ `2Fe + 3H_2 O`

`0,25`         `1/12`               `1/6`                          `(mol)`

`n_[Fe_2 O_3]=32/160=0,2(mol)`

Ta có:`[0,25]/3 < [0,2]/1`

   `=>Fe_2 O_3` dư

`=>m_[Fe]=1/6 . 56~~9,3(g)`

`Zn + H_2 SO_4 -> ZnSO_4 + H_2`

`0,25`     `0,25`                             `0,25`      `(mol)`

`n_[Zn]=[16,25]/65=0,25(mol)`

`a)V_[H_2]=0,25.22,4=5,6(l)`

`b)C_[M_[H_2 SO_4]]=[0,25]/[0,3]~~0,8(M)`

`c)`

`H_2 + 3Fe_2 O_3` $\xrightarrow{t^o}$ `2Fe_3 O_4 + H_2 O`

`1/15`         `0,2`               `2/15`                          `(mol)`

`n_[Fe_2 O_3]=32/160=0,2(mol)`

Ta có:`[0,25]/1 > [0,2]/3`

   `=>H_2` dư

`=>m_[Fe_3 O_4]=2/15 . 232~~30,93(g)`

PTHH: \(Mg+H_2SO_4\rightarrow MgsO_4+H_2\uparrow\)

Ta có: \(n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)=n_{MgSO_4}=n_{H_2SO_4}\) \(\Rightarrow\left\{{}\begin{matrix}m_{MgSO_4}=0,2\cdot120=24\left(g\right)\\V_{H_2}=0,2\cdot22,4=4,48\left(l\right)\\C\%_{H_2SO_4}=\dfrac{0,2\cdot98}{294}\cdot100\%\approx6,67\%\end{matrix}\right.\)