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)

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

Ta có: \(n_{Fe}=\dfrac{0,56}{56}=0,01\left(mol\right)\)

\(PTHH:H_2SO_4+Fe--->FeSO_4+H_2\)

a. Theo PT: \(n_{H_2SO_4}=n_{FeSO_4}=n_{H_2}=n_{Fe}=0,01\left(mol\right)\)

\(\Rightarrow m_{FeSO_4}=0,01.152=1,52\left(g\right)\)

\(V_{H_2}=0,01.22,4=0,224\left(lít\right)\)

b. Ta có: \(m_{H_2SO_4}=0,01.98=0,98\left(g\right)\)

Ta lại có: \(C_{\%_{H_2SO_4}}=\dfrac{0,98}{m_{dd_{H_2SO_4}}}.100\%=19,6\%\)

\(\Rightarrow m_{dd_{H_2SO_4}}=5\left(g\right)\)

a,\(n_{CO_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

PTHH: CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O

Mol:      0,1            0,2                          0,1

\(m_{CaCO_3}=0,1.100=10\left(g\right)\)

b,\(C\%_{ddHCl}=\dfrac{0,2.36,5.100\%}{150}=4,87\%\)

c,m_{dd sau pứ}= 10+150-0,1.44 = 151,2 (g)

\(C\%_{ddCaCl_2}=\dfrac{0,1.111.100\%}{151,2}=7,34\%\)

a)    Fe + H₂SO₄ → FeSO₄ + H₂

_{b)  Ta có :   nH2 = \(\dfrac{16,8}{22,4}\)} = 0,75 (mol)

⇒ n_Fe= 0,75.56 = 42(gam)

Ta có: \(n_{H_2}=\dfrac{16,8}{22,4}=0,75\left(mol\right)\)

a. \(PTHH:Fe+H_2SO_4--->FeSO_4+H_2\uparrow\)

b. Theo PT: \(n_{Fe}=n_{H_2}=0,75\left(mol\right)\)

\(\Rightarrow m_{Fe}=56.0,75=42\left(g\right)\)

\(a,PTHH:Fe+H_2SO_4\to FeSO_4+H_2\\ b,n_{H_2}=\dfrac{16,8}{22,4}=0,74(mol)\\ \Rightarrow n_{Fe}=0,75(mol)\\ \Rightarrow m_{Fe}=0,75.56=42(g)\\ c,n_{H_2SO_4}=\dfrac{245.10\%}{100\%.98}=0,25(mol)\)

Vì \(\dfrac{n_{Fe}}{1}>\dfrac{n_{H_2SO_4}}{1}\) nên \(Fe\) dư

\(n_{Fe(dư)}=0,75-0,25=0,5(mol)\\ \Rightarrow m_{Fe(dư)}=0,5.56=28(g)\)

a)

$Fe + H_2SO_4 \to FeSO_4 + H_2$

b) $n_{Fe} = \dfrac{14}{56} = 0,25(mol)$
Theo PTHH : $n_{H_2SO_4} = n_{Fe} =  0,25(mol)$

$\Rightarrow m_{dd\ H_2SO_4} = \dfrac{0,25.98}{10\%} = 245(gam)$

c)

$n_{H_2} = n_{Fe} = 0,25(mol)$

Sau phản ứng, $m_{dd} = 14 + 245 - 0,25.2 = 258,5(gam)$

$C\%_{FeSO_4} = \dfrac{0,25.152}{258,5}.100\% = 14,7\%$

a,

ⁿFe₂O₃ = 0,05 mol

Fe₂O₃ + H₂SO₄ -------> Fe₂(SO₄)₃ + H₂O

0,05-------> 0,15------------> 0,05 -------->0,15

^mddH₂SO₄ = 150 g

b , ^m Fe₂(SO₄)₃ = 20 g

C phần trăm = \(\dfrac{20}{150}\times100\)= 13,3

\(n_{Fe}=\dfrac{12}{56}=\dfrac{3}{14}\left(mol\right)\)

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

\(\dfrac{3}{14}....\dfrac{3}{14}.......\dfrac{3}{14}......\dfrac{3}{14}\)

\(m_{FeSO_4}=\dfrac{3}{14}\cdot152=32.57\left(g\right)\)

\(V_{H_2}=\dfrac{3}{14}\cdot22.4=4.8\left(l\right)\)

\(m_{dd_{H_2SO_4}}=\dfrac{\dfrac{3}{14}\cdot98}{19.6\%}=107.1\left(g\right)\)