n_Al = 5.4/27 = 0.2  (mol) 

2Al + 3H2SO4 => Al2(SO4)3 + 3H2 

0.2____0.3_________________0.3 

VH2 = 0.3*22.4 = 6.72(l) 

CM H2SO4 = 0.3/0.1 = 3 M

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

Ta có: \(n_{Al}=\dfrac{5,4}{27}=0,2\left(mol\right)\) 

\(\Rightarrow n_{H_2}=0,3mol=n_{H_2SO_4}\) \(\Rightarrow\left\{{}\begin{matrix}V_{H_2}=0,3\cdot22,4=6,72\left(l\right)\\C_{M_{H_2SO_4}}=\dfrac{0,3}{0,1}=3\left(M\right)\end{matrix}\right.\)

a)

$n_{Al} = 0,3(mol)$

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

Theo PTHH : 

$n_{H_2SO_4} = \dfrac{3}{2}n_{Al} = 0,45(mol)$
$m_{dd\ H_2SO_4} = \dfrac{0,45.98}{12,25\%} = 360(gam)$

b)

$n_{H_2} = n_{H_2SO_4} = 0,45(mol)$
$V_{H_2} = 0,45.22,4 = 10,08(lít)$

c)

$n_{Al_2(SO_4)_3} = 0,15(mol)$
$m_{dd\ sau\ pư} = 8,1 + 360 - 0,45.2 = 367,2(gam)$
$C\%_{Al_2(SO_4)_3} = \dfrac{0,15.342}{367,2}.100\% = 14\%$

giúp mk vs

\(n_{H_2}=\dfrac{5,6}{22,4}=0,25(mol)\\ Mg+H_2SO_4\to MgSO_4+H_2\\ MgO+H_2SO_4\to MgSO_4+H_2O\\ \Rightarrow n_{Mg}=0,25(mol)\\ a,\begin{cases} \%_{Mg}=\dfrac{0,25.24}{14}.100\%=42,86\%\\ \%_{MgO}=100\%-42,86\%=57,14\% \end{cases}\\ b,n_{MgO}=\dfrac{14-0,25.24}{40}=0,2(mol)\\ \Rightarrow \Sigma n_{H_2SO_4}=0,2+0,25=0,45(mol)\\ \Rightarrow C\%_{H_2SO_4}=\dfrac{0,45.98}{200}.100\%=22,05\%\)

\(n_{H_2}=\dfrac{1,568}{22,4}=0,07mol\\ n_{Al}=a;n_{Mg}=b\\ 2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\\ Mg+H_2SO_4\rightarrow MgSO_4+H_2\\ \Rightarrow\left\{{}\begin{matrix}27a+24b=1,41\\1,5a+b=0,07\end{matrix}\right.\\ \Rightarrow a=0,03;b=0,025\\ m_{Al}=0,03.27=0,81g\\ m_{Mg}=1,41-0,81=0,6g\)

Bài 1

Bài 5

Fe + 2CH₃COOH \(\rightarrow\) (CH₃COO)₂Fe + H₂(1)

nCH₃COOH = \(\dfrac{4,5}{60}=0,075mol\)

a) THeo pt: n(CH₃COO)₂Fe = \(\dfrac{1}{2}.nCH_3COOH=0,0375mol\)

=> m = 6,525g

c) Theo pt (1) nH₂ = 1/2nCH₃COOH = 0,0375 mol

2H₂ + O₂ \(\xrightarrow[]{t^o}\) 2H₂O

Theo pt: nO₂ = 0,5nH₂ = 0,01875mol

=> VO₂ = 0,42 lít

=> Vkk = 0,42.5 = 2,1 lít

Bạn xem lại đề giúp mình nhé  3,3 lít hay 3,36 lít 

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

PTHH: 2Al + 3H₂SO₄ → Al₂(SO₄)₃ + 3H₂

Mol:     0,1       0,15                                0,15

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

c,\(C_{M_{ddH_2SO_4}}=\dfrac{0,15}{0,5}=0,3M\)

a) B là \(Al_2\left(SO_4\right)_3\), C là \(Cu\)

\(b)n_{H_2}=\dfrac{6,72}{22,4}=0,3mol\\ 2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

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

\(m_{hh}=0,2.27+3,2=8,6g\\ \%m_{Cu}=\dfrac{3,2}{8,6}\cdot100=37,21\%\\ \%m_{Al}=100-37,21=62,79\%\\ c)C_{M_{H_2SO_4}}=\dfrac{0,3}{0,25}=1,2M\)