\(n_{H_2}= \dfrac{8,96}{22,4} = 0,4(mol)\\ 2Al + 6HCl \to 2AlCl_3 + 3H_2\\ Fe + 2HCl \to FeCl_2 + H_2\\ m_{tăng} = m_{kim\ loại} - m_{H_2} = 11 - 0,4.2 = 10,2(gam)\)

PTHH: 

Ta có: 

PTHH: \(2Al+6HCl\rightarrow2AlCl_3+3H_2\uparrow\)

            \(Fe+2HCl\rightarrow FeCl_2+H_2\uparrow\)

Ta có: \(m_{H_2}=\dfrac{8,96}{22,4}\cdot2=0,8\left(g\right)< m_{hh}=11\left(g\right)\)

\(\Rightarrow\) Sau p/ứ dd tăng \(11-0,8=10,2\left(g\right)\)

\(n_{Al}=\dfrac{5.4}{27}=0.2\left(mol\right)\)

\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

\(0.2........0.6.........0.2.........0.3\)

\(V_{dd_{HCl}}=\dfrac{0.6}{2}=0.3\left(l\right)\)

\(m_{AlCl_3}=0.2\cdot133.5=26.7\left(g\right)\)

\(V_{H_2}=0.3\cdot22.4=6.72\left(l\right)\)

\(n_{Fe_2O_3}=\dfrac{32}{160}=0.2\left(mol\right)\)

\(Fe_2O_3+3H_2\underrightarrow{^{t^0}}2Fe+3H_2O\)

\(1..............3\)

\(0.2............0.3\)

\(LTL:\dfrac{0.2}{1}>\dfrac{0.3}{3}\Rightarrow Fedư\)

\(m_{Cr}=m_{Fe_2O_3\left(dư\right)}+m_{Fe}=\left(0.2-0.1\right)\cdot160+0.2\cdot56=27.2\left(g\right)\)

a) 2Al + 6HCl $\to$ 2AlCl3 + 3H2

b)

n Al = 5,4/27 = 0,2(mol)

Theo PTHH : n HCl = 3n Al = 0,6(mol)

=> V = 0,6/2 = 0,3(lít)

n AlCl3 = n Al = 0,2(mol)

=> m = 0,2.133,5 = 26,7(gam)

c) n H2 = 1/2 n HCl = 0,3(mol)

n Fe2O3 = 32/160 = 0,2(mol)

$Fe_2O_3 + 3H_2 \xrightarrow{t^o} 2Fe + 3H_2O$

Ta thấy : n Fe2O3 /1 = 0,2 > n H2 /3 = 0,1 => Fe2O3 dư

Theo PTHH : n H2O = n H2 = 0,3(mol)

Bảo toàn khối lượng : 

m Fe2O3 + m H2 = m chất rắn + m H2O

=> m chất rắn = 32 + 0,3.2 - 0,3.18 = 27,2 gam

Gọi $n_{Na} = a(mol)$

2Na + 2H₂O → 2NaOH + H₂

a...........................a..........0,5a.....(mol)

2Al + 2NaOH + 2H₂O → 2NaAlO₂ + 3H₂

..a...........a............................................1,5a....(mol)

Suy ra : $0,5a + 1,5a = \dfrac{3,36}{22,4} = 0,15 \Rightarrow a = 0,075$

Vậy :

$m = 0,075.23 + 0,075.27 + 1,35 = 5,1(gam)$

Gọi nNa=a(mol)���=�(���)

2Na + 2H₂O → 2NaOH + H₂

a...........................a..........0,5a.....(mol)

2Al + 2NaOH + 2H₂O → 2NaAlO₂ + 3H₂

..a...........a............................................1,5a....(mol)

Suy ra : 

Đáp án B

Chọn B

Chọn B

\(n_{Mg}=0,3\left(mol\right)\)

\(n_{HCl}=0,3\left(mol\right)\)

\(PTHH:Mg+2HCl\rightarrow MgCl_2+H_2\)

...............0,15......0,3..........0,15.....0,15......

- Thấy sau phản ứng HCl phản ứng hết, Mg còn dư ( dư 0,15 mol )

\(\Rightarrow\left\{{}\begin{matrix}m_M=m_{MgCl_2}=14,25\left(g\right)\\V=V_{H_2}=3,36\left(l\right)\end{matrix}\right.\)

PT: \(Mg+2HCl\rightarrow MgCl_2+H_2\)

Ta có: \(n_{Mg}=\dfrac{7,2}{24}=0,3\left(mol\right)\)

\(n_{HCl}=0,2.1,5=0,3\left(mol\right)\)

Xét tỉ lệ: \(\dfrac{0,3}{1}>\dfrac{0,3}{2}\), ta được Mg dư.

Theo PT: \(n_{MgCl_2}=n_{H_2}=\dfrac{1}{2}n_{HCl}=0,15\left(mol\right)\)

\(\Rightarrow\left\{{}\begin{matrix}m_{MgCl_2}=0,15.95=14,25\left(g\right)\\V_{H_2}=0,15.22,4=3,36\left(l\right)\end{matrix}\right.\)

Bạn tham khảo nhé!