\(n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\\ Mg+2HCl\rightarrow MgCl_2+H_2\\ n_{HCl}=2.0,2=0,4\left(mol\right)\\ a,V_{ddHCl}=\dfrac{0,4}{2}=0,2\left(l\right)\\ b,V_{ddMgCl_2}=V_{ddHCl}=0,2\left(l\right)\\ n_{MgCl_2}=n_{Mg}=0,2\left(mol\right)\\ C_{MddMgCl_2}=\dfrac{0,2}{0,2}=1\left(M\right)\)

1:

a) \(n_{Zn}=\dfrac{13}{65}=0,2\left(mol\right)\)

PTHH: \(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\uparrow\)

______0,2------>0,2------------------->0,2_____(mol)

=> \(V_{H_2}=0,2.22,4=4,48\left(l\right)\)

b) \(V_{ddH_2SO_4}=\dfrac{0,2}{1}=0,2\left(l\right)\)

2:

a) 

\(n_{HCl}=2.0,2=0,4\left(mol\right)\)

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

______0,2<------0,4------------------>0,2______(mol)

=> \(m_{Mg}=0,2.24=4,8\left(g\right)\)

b) \(V_{H_2}=0,2.22,4=4,48\left(l\right)\)

Câu 2:

a, \(n_{Fe_2O_3}=\dfrac{6,4}{160}=0,04\left(mol\right)\)

\(n_{H_2SO_4}=0,5.1=0,5\left(mol\right)\)

PT: \(Fe_2O_3+3H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+3H_2O\)

Xét tỉ lệ: \(\dfrac{0,04}{1}< \dfrac{0,5}{3}\), ta được H₂SO₄ dư.

Vậy: Fe₂O₃ tan hết.

b, Theo PT: \(\left\{{}\begin{matrix}n_{Fe_2\left(SO_4\right)_3}=n_{Fe_2O_3}=0,04\left(mol\right)\\n_{H_2SO_4\left(pư\right)}=3n_{Fe_2O_3}=0,12\left(mol\right)\end{matrix}\right.\)

\(\Rightarrow n_{H_2SO_4\left(dư\right)}=0,5-0,12=0,38\left(mol\right)\)

\(\Rightarrow\left\{{}\begin{matrix}C_{M_{Fe_2\left(SO_4\right)_3}}=\dfrac{0,04}{0,5}=0,08\left(M\right)\\C_{M_{H_2SO_4\left(dư\right)}}=\dfrac{0,38}{0,5}=0,76\left(M\right)\end{matrix}\right.\)

Câu 3:

a, \(n_{Ba\left(OH\right)_2}=0,2.1=0,2\left(mol\right)\)

\(n_{H_2SO_4}=0,3.0,72=0,216\left(mol\right)\)

PT: \(Ba\left(OH\right)_2+H_2SO_4\rightarrow BaSO_{4\downarrow}+2H_2O\)

Xét tỉ lệ: \(\dfrac{0,2}{1}< \dfrac{0,216}{1}\), ta được H₂SO₄ dư.

Theo PT: \(n_{BaSO_4}=n_{Ba\left(OH\right)_2}=0,2\left(mol\right)\Rightarrow m_{BaSO_4}=0,2.233=46,6\left(g\right)\)

b, Theo PT: \(n_{H_2SO_4\left(pư\right)}=n_{Ba\left(OH\right)_2}=0,2\left(mol\right)\Rightarrow n_{H_2SO_4\left(dư\right)}=0,216-0,2=0,016\left(mol\right)\)

\(\Rightarrow C_{M_{H_2SO_4\left(dư\right)}}=\dfrac{0,016}{0,2+0,3}=0,032\left(M\right)\)

c, - Nhúng quỳ tím vào dd thấy quỳ hóa đỏ do H₂SO₄ dư.

200ml = 0,2l

\(n_{Ba\left(OH\right)2}=0,5.0,2=0,1\left(mol\right)\)

Pt : \(Ba\left(OH\right)_2+2HCl\rightarrow BaCl_2+2H_2O|\)

              1              2             1            2

             0,1           0,2          0,1

a) \(n_{HCl}=\dfrac{0,1.2}{1}=0,2\left(mol\right)\)

\(V_{ddHCl}=\dfrac{0,2}{1}=0,2\left(l\right)=200\left(ml\right)\)

b) \(n_{BaCl2}=\dfrac{0,2.1}{2}=0,1\left(mol\right)\)

⇒ \(m_{BaCl2}=0,1.208=20,8\left(g\right)\)

c) \(V_{ddspu}=0,2+0,2=0,4\left(l\right)\)

\(C_{M_{BaCl2}}=\dfrac{0,1}{0,4}=0,25\left(M\right)\)

 Chúc bạn học tốt

PTHH: \(Ba\left(OH\right)_2+2HCl\rightarrow BaCl_2+2H_2O\)

Ta có: \(n_{Ba\left(OH\right)_2}=0,2\cdot0,5=0,1\left(mol\right)\)

\(\Rightarrow\left\{{}\begin{matrix}n_{HCl}=0,2\left(mol\right)\\n_{BaCl_2}=0,1\left(mol\right)\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}V_{ddHCl}=\dfrac{0,2}{1}=0,2\left(l\right)=200\left(ml\right)\\m_{BaCl_2}=0,1\cdot208=20,8\left(g\right)\\C_{M_{BaCl_2}}=\dfrac{0,1}{0,2+0,2}=0,25\left(M\right)\end{matrix}\right.\)

a,\(n_{HCl}=0,2.1=0,2\left(mol\right)\)

PTHH: Fe + 2HCl → FeCl₂ + H₂

Mol:    0,1      0,2        0,1

 \(\Rightarrow m_{Fe}=0,1.56=5,6\left(g\right)\)

b,\(C_{M_{ddFeCl_2}}=\dfrac{0,1}{0,2}=0,5M\)

\(n_{H_2SO_4}=0,2.1=0,2\left(mol\right)\\ Fe+H_2SO_4\rightarrow FeSO_4+H_2\\ 0,2.......0,2.........0,2.......0,2\left(mol\right)\\ m=m_{Fe}=0,2.56=11,2\left(g\right)\\ b.V_{ddFeSO_4}=V_{ddH_2SO_4}=200\left(ml\right)=0,2\left(l\right)\\ C_{MddFeSO_4}=\dfrac{0,2}{0,2}=1\left(M\right)\)