a,\(m_{BaCl_2}=208.15\%=31,2\left(g\right)\Rightarrow n_{BaCl_2}=\dfrac{31,2}{208}=0,15\left(mol\right)\)

\(m_{H_2SO_4}=150.19,6\%=29,4\left(g\right)\Rightarrow n_{H_2SO_4}=\dfrac{29,4}{98}=0,3\left(mol\right)\)

PTHH: BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl

Mol:      0,15       0,15          0,15        0,3

Ta có: \(\dfrac{0,15}{1}< \dfrac{0,3}{1}\) ⇒ BaCl₂ hết, H₂SO₄ dư

\(m_{H_2SO_4dư}=\left(0,3-0,15\right).98=14,7\left(g\right)\)

b, \(m_{BaSO_4}=0,15.233=34,95\left(g\right)\)

  \(m_{HCl}=0,3.36,5=10,95\left(g\right)\)

PTHH: \(CuSO_4+2NaOH\rightarrow Na_2SO_4+Cu\left(OH\right)_2\downarrow\)

Ta có: \(\left\{{}\begin{matrix}n_{CuSO_4}=0,08\cdot3,5=0,28\left(mol\right)\\n_{NaOH}=0,12\cdot1,5=0,18\left(mol\right)\end{matrix}\right.\)

Xét tỉ lệ: \(\dfrac{0,28}{1}>\dfrac{0,18}{2}\) \(\Rightarrow\) CuSO₄ còn dư

\(\Rightarrow\left\{{}\begin{matrix}n_{Na_2SO_4}=0,09\left(mol\right)=n_{Cu\left(OH\right)_2}\\n_{CuSO_4\left(dư\right)}=0,19\left(mol\right)\\\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}m_{Na_2SO_4}=0,09\cdot142=12,78\left(g\right)\\m_{Cu\left(OH\right)_2}=0,09\cdot98=8,82\left(g\right)\\m_{CuSO_4\left(dư\right)}=0,19\cdot160=30,4\left(g\right)\end{matrix}\right.\)

Mặt khác: \(\left\{{}\begin{matrix}C_{M_{Na_2SO_4}}=\dfrac{0,09}{0,08+0,12}=0,45\left(M\right)\\C_{M_{CuSO_4\left(dư\right)}}=\dfrac{0,19}{0,08+0,12}=0,95\left(M\right)\end{matrix}\right.\)

\(n_{BaCl_2}=\dfrac{31,2}{208}=0,15mol\)

\(BaCl_2+H_2SO_4\rightarrow BaSO_4\downarrow+2HCl\)

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

a)\(m_{BaSO_4}=0,15\cdot233=34,95\left(g\right)\)

b)\(m_{H_2SO_4}=0,15\cdot98=14,7\left(g\right)\)

    \(\Rightarrow m_{ddH_2SO_4}=\dfrac{14,7}{19,6}\cdot100=75\left(g\right)\)

c)\(m_{HCl}=0,3\cdot36,5=10,95\left(g\right)\)

  \(m_{ddsau}=31,2+75-34,95=71,25\left(g\right)\)

  \(\Rightarrow C\%_{HCl}=\dfrac{10,95}{71,25}\cdot100\%=15,37\%\)

Câu 4 : 

\(n_{SO2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

Pt : \(SO_2+Ba\left(OH\right)_2\rightarrow BaSO_3+H_2O|\) 

        1              1                  1            1

     0,15          0,15             0,15

a) \(n_{Ba\left(OH\right)2}=\dfrac{0,15.1}{1}=0,15\left(mol\right)\)

⇒ \(m_{Ba\left(OH\right)2}=0,15.171=25,65\left(g\right)\)

\(C_{ddBa\left(OH\right)2}=\dfrac{25,65.100}{150}=17,1\)⁰/₀

b) \(n_{BaSO3}=\dfrac{0,15.1}{1}=0,15\left(mol\right)\)

⇒ \(m_{BaSO3}=0,15.217=32,55\left(g\right)\)

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

                  1               2            1              2

                0,15          0,3

\(n_{HCl}=\dfrac{0,15.2}{1}=0,3\left(mol\right)\)

\(m_{HCl}=0,3.36,5=10,95\left(g\right)\)

\(m_{ddHCl}=\dfrac{10,95.100}{20}=54,75\left(g\right)\)

\(V_{ddHCl}=\dfrac{54,75}{1,2}=45,625\left(ml\right)\)

 Chúc bạn học tốt

\(n_{BaCl_2}=\dfrac{150.16,64\%}{137+35.2}=0,12\left(mol\right)\)

\(n_{H_2SO_4}=\dfrac{100.14,7\%}{98}=0,15\left(mol\right)\)

Phương trình hóa học : 

BaCl₂ + H₂SO₄ -----> BaSO₄ + 2HCl 

Dễ thấy \(\dfrac{n_{BaCl_2}}{1}< \dfrac{n_{H_2SO_4}}{1}\Rightarrow H_2SO_4\text{ dư }0,15-0,12=0,03\left(mol\right)\)

c) Khối lượng kết tủa : 

\(m_{BaSO_4}=0,12.233=27,96\) (g) 

Khối lượng chất tan : \(m_{HCl}=0,24.36,5=8,76\left(g\right)\) ; 

\(m_{H_2SO_4\left(\text{dư}\right)}=0,03.98=2,94\left(g\right)\) 

c) \(C\%_{H_2SO_4}\)= \(\dfrac{2,94}{150+100}.100\%=1,176\%\)

_{\(C\%_{HCl}=\dfrac{8,76}{150+100}.100\%=3.504\%\)}

d) NaOH + HCl ---> NaCl + H₂O 

      0,24 <-- 0,24

       mol       mol

    2NaOH + H₂SO₄  ---> Na₂SO₄ + 2H₂O

  0,06 mol <-- 0,03 mol  

\(\Rightarrow n_{NaOH}=0,24+0,06=0,3\left(mol\right)\)

\(V_{NaOH}=0,3.2=0,6\left(l\right)\)

a. PTHH    BaCl2 + H2SO4 → BaSO4↓ + 2HCl

b. _ mBaCl2 = 16,61.150:100 = 24,96 g

nBaCl2 = 24.96:208 = 0,12 mol

_ mH2SO4 = 14,7.100:100 = 14,7 g

nH2SO4 = 14,7:98 = 0,15 mol

Ta thấy: nBaCl2 < nH2SO4 ⇒ BaCl2 hết, H2SO4 dư