\(a,PTHH:4Al+3O_2\rightarrow^{t^o}2Al_2O_3\\ b,n_{Al_2O_3}=\dfrac{40,8}{102}=0,4\left(mol\right)\\ \Rightarrow n_{Al}=2n_{Al_2O_3}=0,8\left(mol\right)\\ \Rightarrow m_{Al}=0,8\cdot27=21,6\left(g\right)\\ b,n_{O_2}=\dfrac{3}{2}n_{Al_2O_3}=0,6\left(mol\right)\\ \Rightarrow V_{O_2\left(đktc\right)}=0,6\cdot22,4=13,44\left(l\right)\)

\(n_{Al}=\dfrac{13,5}{27}=0,5\left(mol\right)\\ n_{O_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\\ pthh:4Al+3O_2\underrightarrow{t^o}2Al_2O_3\) 
\(LTL:\dfrac{0,5}{4}< \dfrac{0,4}{3}\) 
=> Oxi dư , Al hết 
\(n_{O_2\left(p\text{ư}\right)}=\dfrac{3}{4}n_{Al}=0.375\left(mol\right)\) 
\(n_{O_2\left(d\right)}=0,4-0,375=0,025\left(mol\right)\)
\(n_{Al_2O_3}=\dfrac{1}{2}n_{Al}=0,25\left(mol\right)\\ m_{Al_2O_3}=0,25.102=25,5g\)

\(n_{H_2}=\dfrac{3,72}{24,79}=0,15mol\)

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

0,15    0,3                       0,15  ( mol )

\(m_{Zn}=0,15.65=9,75g\)

\(m_{HCl}=0,3.36,5=10,95g\)

\(n_{Fe}=\dfrac{28}{56}=0,5\left(mol\right)\)

a) Pt : \(Fe+2HCl\rightarrow FeCl_2+H_2|\)

            1          2            1           1

           0,5        1                        0,5

b) \(n_{HCl}=\dfrac{0,5.2}{1}=1\left(mol\right)\)

⇒ \(m_{HCl}=1.36,5=36,5\left(g\right)\)

c) \(n_{H2}=\dfrac{1.1}{2}=0,5\left(mol\right)\)

\(V_{H2\left(dktc\right)}=0,5.22,4=11,2\left(l\right)\)

 Chúc bạn học tốt

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 :

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

\(n_{Al}=\dfrac{13,5}{27}=0,5\left(mol\right)\\a, 4Al+3O_2\rightarrow\left(t^o\right)2Al_2O_3\\ n_{O_2}=\dfrac{3}{4}.0,5=0,375\left(mol\right)\\ m_{O_2}=32.0,375=12\left(g\right)\\ V_{O_2\left(đktc\right)}=0,375.22,4=8,4\left(l\right)\)

PTHH:

2KMnO₄ -to> K₂MnO₄ + MnO₂ + O₂

0,2------------------------------------------0,1

n KMnO4=\(\dfrac{31,6}{158}\)=0,2 mol

=>VO2=0,1.22,4=2,24l

b)2Mg+O₂-to>2MgO

     0,2----0,1----0,2

n Mg=\(\dfrac{7,2}{24}\)=0,3 mol

=>Mg dư :0,1 mol

=>mMg=0,1.24=2,4g

=>m MgO=0,2.40=8g

n Al=\(\dfrac{32,4}{27}\)=1,2 mol

n O2=\(\dfrac{23,7984}{22,4}\)=1,062mol

4Al+3O₂-to>2Al₂O₃

1,2---------------0,6 mol

O2 dư

=>m _Al2O3=0,6.102=61,2g

2Al+6HCl->2AlCl₃+3H₂

1,2-----------------------1,8 mol

=>V_H2=1,8.22,4=40,32l

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)