Câu 7 : 

\(n_{H2}=\dfrac{17,92}{22,4}=0,8\left(mol\right)\)

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

         2            3                 1              3

       \(\dfrac{8}{15}\)         0,8                \(\dfrac{4}{15}\)         0,8

\(n_{H2SO4}=\dfrac{0,8.3}{3}=0,8\left(mol\right)\)

⇒ \(m_{H2SO4}=0,8.98=78,4\left(g\right)\)

\(n_{Al2\left(SO4\right)3}=\dfrac{0,8.1}{3}=\dfrac{4}{15}\left(mol\right)\)

⇒ \(m_{Al2\left(SO4\right)3}=\dfrac{4}{15}.342=91,2\left(g\right)\)

\(n_{Al}=\dfrac{0,8.2}{3}=\dfrac{8}{15}\left(mol\right)\)

⇒ \(m_{Al}=\dfrac{8}{15}.27=14,4\left(g\right)\)

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bài 8

Al₂O₃+6HNO₃->2Al(NO₃)₃+3H₂

\(\dfrac{2}{15}\)------------0,8-------\(\dfrac{4}{15}\)----------0,4 mol

n _H2O=\(\dfrac{7,2}{18}\)=0,4 mol

=>m _Al2O3=\(\dfrac{2}{15}\).102=13,6g

=>m _HNO3=0,8.63=50,4g

=>m _Al(NO3)3=\(\dfrac{4}{15}\).213=56,8g

Bài 7

2Al+3H₂SO₄->Al₂(SO₄)₃+3H₂

\(\dfrac{8}{15}\)------0,5-----------\(\dfrac{4}{15}\)--------0,8

n H2=\(\dfrac{17,92}{22,4}\)=0,8 mol

=>m Al= \(\dfrac{8}{15}\).27=14,4g

=>m HCl=0,5.36,5=18,25g

=>m Al2(SO4)3=\(\dfrac{4}{15}\).342=91,2g

a, PT: \(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

Ta có: \(n_{H_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

Theo PT: \(n_{HCl}=2n_{H_2}=0,6\left(mol\right)\)

\(\Rightarrow m_{HCl}=0,6.36,5=21,9\left(g\right)\)

b, Theo PT: \(n_{Al}=\dfrac{2}{3}n_{H_2}=0,2\left(mol\right)\)

\(\Rightarrow m_{Al}=0,2.27=5,4\left(g\right)\)

nH₂=6.72/22,4=0,3(mol)
PTHH: 2Al +   6HCl --> 2AlCl₃ + 3H₂
bài ra:  0,2 <-- 0,6  <--   0,2   <-- 0,3  /mol
a) mHCl = 0,6.36,5=21,9(g)
b) mAl = 0.2.24 = 4,8(g)
 

\(PTHH:2Al+6HCl->2AlCl_3+3H_2\)

              0,2<--0,6<----------0,2<------0,3    (mol)

\(n_{H_2\left(dktc\right)}=\dfrac{V}{22,4}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

\(m_{HCl}=n\cdot M=0,6\cdot\left(1+35,5\right)=21,9\left(g\right)\)

\(m_{AlCl_3}=n\cdot M=0,2\cdot\left(27+35,5\cdot3\right)=26,7\left(g\right)\)

a, PT: 

Ta có: nAl=23nH2=0,2(mol)

⇒mAl=0,2.27=5,4(g)

a, PT: 

Ta có: nAl=23nH2=0,2(mol)

⇒mAl=0,2.27=5,4(g)

a.b.c.\(n_{Al}=\dfrac{2,7}{27}=0,1mol\)

\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

0,1                         0,1      0,15   ( mol )

\(V_{H_2}=0,15.22,4=3,36l\)

\(m_{AlCl_3}=0,1.133,5=13,35g\)

d.\(Fe_2O_3+3H_2\rightarrow\left(t^o\right)2Fe+3H_2O\)

                  0,15              0,1              ( mol )

\(m_{Fe}=0,1.56=5,6g\)

a: \(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

b: \(n_{AlCl_3}=\dfrac{26.7}{27+35.5\cdot3}=0.2\left(mol\right)\)

=>n_Al=0,2(mol)

\(m=0.2\cdot27=5.4\left(g\right)\)

c: \(2\cdot n_{Al}=3\cdot n_{H_2}\Leftrightarrow n_{H_2}=\dfrac{2}{3}\cdot\dfrac{1}{5}=\dfrac{2}{15}\left(mol\right)\)

\(V=\dfrac{2}{15}\cdot22.4=\dfrac{224}{75}\left(lít\right)\)

a) \(PTHH:2Al+6HCl\xrightarrow[]{}2AlCl_3+3H_2\)

b) \(n_{H_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

\(n_{Al}=\dfrac{0,15.2}{3}=0,1\left(mol\right)\)

\(m_{Al}=0,1.27=2,7\left(g\right)\)

c)\(n_{AlCl_3}=\dfrac{0,15.2}{3}=0,1\left(mol\right)\)

\(m_{AlCl_3}=0,1.133,5=13,35\left(g\right)\)

pls help me mng ơi!Tuần sau mnh thi mất r!T_T

a, 2Al + 6HCl -> 2AlCl₃ + 3H₂  (1)

b, n_H2=\(\dfrac{V}{22.4}\)=\(\dfrac{3,36}{22,4}\)=0,15 (mol)

Từ pt (1)

-> n_Al=\(\dfrac{2}{3}\).n_H2 = \(\dfrac{2}{3}\).0,15 = 0,1 (mol)

-> m_Al = n.M = 0,1 . 27 = 2,7 (g)

c, Từ pt (1)

-> n_AlCl3= \(\dfrac{2}{3}\).n_H2 = \(\dfrac{2}{3}\). 0,15 = 0,1 (mol)

-> m_AlCl3= n.M = 0,1 .133.5 = 13,35 (g)

a) \(n_{H_2}=\dfrac{13,44}{22,4}=0,6\left(mol\right)\)

PTHH: 2Al + 6HCl ---> 2AlCl₃ + 3H₂

Theo PTHH: \(n_{AlCl_3}=n_{Al}=\dfrac{2}{3}.n_{H_2}=\dfrac{2}{3}.0,6=0,4\left(mol\right)\)

=> m_Al = 0,4.27 = 10,8 (g)

b) \(m_{AlCl_3}=0,4.133,5=53,4\left(g\right)\)