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

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

\(\Rightarrow\left\{{}\begin{matrix}n_{H_2SO_4}=0,15\left(mol\right)=n_{H_2}\\n_{Al_2\left(SO_4\right)_3}=0,05\left(mol\right)\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}m_{H_2SO_4}=0,15\cdot98=14,7\left(g\right)\\m_{Al_2\left(SO_4\right)_3}=0,05\cdot342=17,1\left(g\right)\\V_{H_2}=0,15\cdot22,4=3,36\left(l\right)\end{matrix}\right.\)

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

PTHH: 2Al + 3H₂SO₄ --> Al₂(SO₄)₃ + 3H₂

______0,1--->0,15-------->0,05------->0,15

=> m_H2SO4 = 0,15.98 = 14,7 (g)

b) V_H2 = 0,15.22,4 = 3,36 (l)

c) m_Al2(SO4)3 = 0,05.342 = 17,1 (g)

a)

b)

Theo PTHH : 

c)

Theo PT trên : 

a)

\(2Al + 3H_2SO_4 \to Al_2(SO_4)_3 + 3H_2\)

b)

\(n_{H_2} = \dfrac{6.13,44}{22,4} = 3,6(mol)\)

Theo PTHH : 

\(n_{Al} = \dfrac{2}{3}n_{H_2} = 2,4(mol)\\ \Rightarrow m_{Al} = 2,4.27 = 64,8(gam)\)

c)

\(4Al + 3O_2 \xrightarrow{t^o} 2Al_2O_3\)

Theo PT trên : 

\(n_{O_2} = \dfrac{3}{4}n_{Al} = 1,8(mol)\\ \Rightarrow V_{O_2} = 1,8.22,4 = 40,32(lít)\)

nAl = 5.4/27 = 0.2 mol 

2Al + 3H2SO4 => Al2(SO4)3 + 3H2 

0.2______________0.1________0.3 

VH2 = 0.3*22.4 = 6.72 (l) 

mAl2(SO4)3 = 0.1*342 = 34.2 g 

Đề sai nha bạn

Ta có: \(n_{H_2}=\dfrac{74,37}{24,79}=3\left(mol\right)\)

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

a, \(n_{Al}=\dfrac{2}{3}n_{H_2}=2\left(mol\right)\)

\(\Rightarrow m_{Al}=2.27=54\left(g\right)\)

b, \(n_{H_2SO_4}=n_{H_2}=3\left(mol\right)\)

\(\Rightarrow m_{H_2SO_4}=3.98=294\left(g\right)\)

\(n_{Zn}=0,4\left(mol\right)\)

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

0,4-----0,8--------------------0,4 (mol)

\(V_{H_2}=0,4.22,4=8,96\left(l\right)\)

\(m_{HCl}=0,8.36,5=29,2\left(g\right)\)

a)

\(n_{Fe} = \dfrac{14}{56} = 0,25(mol)\)

Phương trình hóa học : \(Fe + H_2SO_4 \to FeSO_4 + H_2\)

Theo PTHH : \(n_{H_2} = n_{Fe} = 0,25(mol)\\ \Rightarrow V_{H_2} = 0,25.22,4 = 5,6(lít)\)

b)

Có : \(n_{H_2SO_4} = n_{H_2} = 0,25(mol)\\ \Rightarrow m_{H_2SO_4} = 0,25.98 = 24,5(gam)\)

PT: \(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)

Ta có: \(n_{Fe}=\dfrac{14}{56}=0,25\left(mol\right)\)

Theo PT: \(n_{H_2}=n_{H_2SO_4}=n_{Fe}=0,25\left(mol\right)\)

a, \(V_{H_2}=0,25.22,4=5,6\left(l\right)\)

b, \(m_{H_2SO_4}=0,25.98=24,5\left(g\right)\)

Bạn tham khảo nhé!

nFe = \(\dfrac{14}{56}\)= 0,25 mol

                                Fe  +    H₂SO₄   →  FeSO₄   + H₂ 

Theo pt :                    1            1                 1           1          mol

Theo đề bài :           0,25       0,25            0,25       0,25      mol

=> V H₂ = 0,25 . 22,4 = 5,6 lít

mH₂SO₄  = 0,25 . 98 = 24,5 gam