\(4.a/n_{Al}=\dfrac{5,4}{27}=0,2mol\\ 2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

0,2       0,3                  0,1                  0,3

\(V_{H_2}=0,3.24,79=7,437l\\ b/C_{\%H_2SO_4}=\dfrac{0,3.98}{150}\cdot100=19,6\%\\ c/m_{Al_2\left(SO_4\right)_3}=0,1.342=34,2g\)

\(5.a/n_{MgO}=\dfrac{4}{40}=0,1mol\\ MgO+2HCl\rightarrow MgCl_2+H_2O\)

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

\(C_{\%HCl}=\dfrac{0,2.36,5}{200}\cdot100=3,65\%\\ b/C_{\%MgCl_2}=\dfrac{0,1.95}{200+4}\cdot100=4,66\%\\ c/NaOH+HCl\rightarrow NaCl+H_2O\\ n_{NaOH}=n_{HCl}=0,2mol\\ V_{NaOH}=\dfrac{0,2}{1}=0,2l=200ml\)

\(4.\\ a/n_{Al}=\dfrac{5,4}{27}=0,2mol\\2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

\(0,2......0,3............0,1...............0,3\)

\(V_{H_2}=0,3.24,79=7,437l\\ b.C_{\%H_2SO_4}=\dfrac{0,3.98}{150}\cdot100=19,6\%\\ c.m_{Al_2\left(SO_4\right)_3}=0,1.342=34,2g\)

\(7.\\a) n_{H_2SO_4}=\dfrac{100.9,8}{100.98}=0,1mol\\ ZnO+H_2SO_4\rightarrow ZnSO_4+H_2O\\ n_{ZnO}=n_{ZnSO_4}=n_{H_2SO_4}=0,1mol\\ m_{ZnO}=0,1.81=8,1g\\ b)C_{\%ZnSO_4}=\dfrac{0,1.161}{8,1+100}\cdot100=14,8\%\)

\(9.\\ a)n_{H_2}=\dfrac{2,479}{24,79}=0,1mol\\ Mg+2HCl\rightarrow MgCl_2+H_2\)

\(0,1.....0,2.........0,1........0,1\)

\(m_{Mg}=0,1.24=2,4g\\ m_{MgO}=8,4-2,4=6g\\ b)n_{MgO}=\dfrac{6}{40}=0,15mol\\ MgO+2HCl\rightarrow MgCl_2+H_2O\\ n_{HCl}=0,15.2+0,2=0,5mol\\ m_{ddHCl}=\dfrac{0,5.36,5}{3,65}\cdot100=500g\)

\(n_{Mg}=\dfrac{2,4}{24}=0,1\left(mol\right)\)

PTHH :

\(Mg+H_2SO_4\rightarrow MgSO_4+H_2\uparrow\)

0,1        0,1             0,1             0,1 

\(a,m_{MgSO_4}=0,1.120=12\left(g\right)\)

\(b,V_{H_2}=0,1.22,4=2,24\left(l\right)\)

\(c,m_{ddH_2SO_4}=\dfrac{0,1.98.100}{10}=98\left(g\right)\)

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

Ta có: \(n_{H_2}=\dfrac{3,7185}{24,79}=0,15\left(mol\right)\)

a, \(n_{Al}=\dfrac{2}{3}n_{H_2}=0,1\left(mol\right)\Rightarrow m_{Al}=0,1.27=2,7\left(g\right)\)

b, \(n_{Al_2\left(SO_4\right)_3}=\dfrac{1}{3}n_{H_2}=0,05\left(mol\right)\)

\(\Rightarrow m_{Al_2\left(SO_4\right)_3}=0,05.342=17,1\left(g\right)\)

c, \(n_{H_2SO_4}=n_{H_2}=0,15\left(mol\right)\)

\(\Rightarrow V_{H_2SO_4}=\dfrac{0,15}{1,5}=0,1\left(l\right)=100\left(ml\right)\)

\(n_{Al}=\dfrac{2,7}{27}=0,1mol\\ a.2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

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

\(b.V_{H_2}=0,15.24,79=3,7185l\\ c.m_{Al_2\left(SO_4\right)_3}=0,05.342=17,1g\\ d.C_{M_{H_2SO_4}}=\dfrac{0,15}{0,4}=0,375M\)

D

a) 2Al+6HCl2AlCl3+3H2

b)

nAl==0,4(mol)

nAlCl3=nAl=0,4(mol)

mAlCl3=0,4.133,5=53,4(g)

c)

nH2=nAl=0,6(mol)

VH2=22,4.0,6=13,44(l)

d) n HCl=0,4.6\2=1,2 mol

=>Cm HCl=1,2\0,1=12M

\(n_{Al}=\dfrac{10,8}{27}=0,4\left(mol\right)\)

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

            2           6              2            3

          0,4         1,2           0,4          0,6

b) \(n_{H2}=\dfrac{0,4.3}{2}=0,6\left(mol\right)\)

\(V_{H2\left(dktc\right)}=0,6.24,79=14,874\left(l\right)\)

c)  \(n_{AlCl3}=\dfrac{0,6.2}{3}=0,4\left(mol\right)\)

⇒ \(m_{AlCl3}=0,4.133,5=53,4\left(g\right)\)

d) \(n_{HCl}=\dfrac{0,4.6}{2}=1,2\left(mol\right)\)

100ml = 0,1l

\(C_{M_{ddHCl}}=\dfrac{1,2}{0,1}=12\left(M\right)\)

 Chúc bạn học tốt

a) Mg + H₂SO₄ --> MgSO₄ + H₂

b) \(n_{Mg}=\dfrac{14,4}{24}=0,6\left(mol\right)\)

PTHH: Mg + H₂SO₄ --> MgSO₄ + H₂

           0,6--->0,6------->0,6----->0,6

=> \(m_{H_2SO_4}=0,6.98=58,8\left(g\right)\)

c) 

PTHH: 2H₂ + O₂ --t^o--> 2H₂O

           0,6-->0,3

=> V_O2 = 0,3.24,79 = 7,437 (l)

=> V_kk = 7,437.5 = 37,185 (l)

b) m_H2SO4 ban đầu là bao nhiêu :) ?