\(n_{CO_2}=\dfrac{4.48}{22.4}=0.2\left(mol\right)\)

\(n_{NaOH}=\dfrac{8}{40}=0.2\left(mol\right)\)

\(T=\dfrac{0.2}{0.2}=1\)

\(\Rightarrow\text{Tạo muối axit}\)

\(NaOH+CO_2\rightarrow NaHCO_3\)

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

\(m_{NaHCO_3}=0.2\cdot84=16.8\left(g\right)\)

Ta có: \(n_{CO_2}=0,2\left(mol\right)\)

\(n_{NaOH}=\dfrac{8}{40}=0,2\left(mol\right)\)

\(\Rightarrow\dfrac{n_{NaOH}}{n_{CO_2}}=1\) ⇒ Pư tạo muối NaHCO₃.

PT: \(CO_2+NaOH\rightarrow NaHCO_3\)

___0,2________________0,2 (mol)

⇒ m_NaHCO3 = 0,2.84 = 16,8 (g)

Bạn tham khảo nhé!

\(\dfrac{nNaOH}{nCO2}=\dfrac{\dfrac{8}{40}}{\dfrac{4,48}{22,4}}=1\)=>tạo muối NaHCO3

pthh CO2+NaOH->NaHCO3=>nNaHCO3=NCO2=0,2mol

=>mNaHCO3=0,2.84=16,8 g

Bài 1: 

Ta có: \(\left\{{}\begin{matrix}n_{CO_2}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\\n_{NaOH}=\dfrac{164\cdot1,22\cdot20\%}{40}=1,0004\left(mol\right)\end{matrix}\right.\) \(\Rightarrow\) Tạo muối trung hòa

PTHH: \(CO_2+2NaOH\rightarrow Na_2CO_3+H_2O\)

Vì NaOH dư nên tính theo CO₂ \(\Rightarrow\left\{{}\begin{matrix}n_{Na_2CO_3}=0,25\left(mol\right)\\n_{NaOH\left(dư\right)}=0,5004\left(mol\right)\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}m_{Na_2CO_3\left(rắn\right)}=0,25\cdot106=26,5\left(g\right)\\m_{NaOH\left(rắn\right)}=0,5004\cdot40=20,016\left(g\right)\end{matrix}\right.\)

*Các bài còn lại bạn làm theo gợi ý bên dưới 
PTHH: \(CO_2+NaOH\rightarrow NaHCO_3\)  (1)

            \(CO_2+2NaOH\rightarrow Na_2CO_3+H_2O\)  (2)

\(n_{SO_2} = \dfrac{4,48}{22,4} = 0,2(mol) ; n_{NaOH} = 0,25(mol)\\ 1<\dfrac{n_{NaOH}}{n_{SO_2}} = \dfrac{0,25}{0,2} = 1,25 <2 \to Muối\ tạo\ thành : NaHSO_3(a\ mol) ; Na_2SO_3(b\ mol)\\ n_{SO_2} = a + b = 0,2(mol)\\ n_{NaOH} = a + 2b = 0,25(mol)\\ \Rightarrow a = 0,15 ; b = 0,05\\ m_{NaHSO_3} = 0,15.104 = 15,6(gam) \\ m_{Na_2SO_3} = 0,05.126 = 6,3(gam)\)

\(n_{SO_2}=\dfrac{4,2}{22,4}=0,1875\left(mol\right)\)

n_KOH = 0,275 (mol)

PTHH: 2KOH + SO₂ --> K₂SO₃ + H₂O

_____0,275-->0,1375->0,1375

K₂SO₃ + SO₂ + H₂O --> 2KHSO₃

0,05<---0,05------------->0,1

=> \(\left\{{}\begin{matrix}m_{KHSO_3}=0,1.120=12\left(g\right)\\m_{K_2SO_3}=\left(0,1375-0,05\right).158=13,825\left(g\right)\end{matrix}\right.\)

nSO2=4,2/22,4=0,1875(mol)nSO2=4,222,4=0,1875(mol)

n_KOH = 0,275 (mol)

PTHH: 2KOH + SO₂ --> K₂SO₃ + H₂O

_____0,275-->0,1375->0,1375

K₂SO₃ + SO₂ + H₂O --> 2KHSO₃

0,05<---0,05------------->0,1

=> {mKHSO3=0,1.120=12(g)mK2SO3=(0,1375−0,05).158=13,825(g)

a/ \(n_{SO_2}=\dfrac{3,08}{22,4}=0,1375\left(mol\right);n_{H_2}=\dfrac{1,68}{22,4}=0,075\left(mol\right)\)

2Fe + 6H₂SO₄(đ) ---t^o---> Fe₂(SO₄)₃ + 6SO₂ + 3H₂O

  x                                                              3x

Cu + 2H₂SO₄(đ) ---t^o---> CuSO₄ + SO₂ + 2H₂O

 y                                                      y

Fe + 2HCl ----> FeCl₂ + H₂

x                                     x

Cu + 2HCl -----> CuCl₂ + H₂

y                                          y

Ta có hệ pt: \(\left\{{}\begin{matrix}3x+y=0,1375\\x+y=0,075\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=0,03125\left(mol\right)\\y=0,04375\left(mol\right)\end{matrix}\right.\)

\(m_{hh}=0,03125.56+0,04375.64=4,55\left(g\right)\)

\(\%m_{Fe}=\dfrac{0,03125.56.100\%}{4,55}=38,46\%\)

b, \(n_{Ba\left(OH\right)_2}=0,1.1,2=0,12\left(mol\right)\)

Ta có: \(T=\dfrac{n_{SO_2}}{n_{Ba\left(OH\right)_2}}=\dfrac{0,1375}{0,12}=1,1458\) 

 => tạo ra 2 muối là BaSO₃ và Ba(HSO₃)₂

SO₂ + Ba(OH)₂ ---> BaSO₃ + H₂O

 x          x                      x

2SO₂ + Ba(OH)₂ ----> Ba(HSO₃)₂

   y           0,5y                 0,5y

Ta có hệ pt: \(\left\{{}\begin{matrix}x+y=0,1375\\x+0,5y=0,12\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=0,1025\left(mol\right)\\y=0,035\left(mol\right)\end{matrix}\right.\)

\(m_{muối}=0,1025.217+0,5.0,035.299=27,475\left(g\right)\)

*Sửa đề: "25,65 gam Ba(OH)₂"

Ta có: \(\left\{{}\begin{matrix}n_{SO_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\\n_{Ba\left(OH\right)_2}=\dfrac{25,65}{171}=0,15\left(mol\right)\end{matrix}\right.\) \(\Rightarrow\) Tạo 2 muối

PTHH: \(SO_2+Ba\left(OH\right)_2\rightarrow BaSO_3\downarrow+H_2O\)

                a_________a_________a                       (mol)

            \(2SO_2+Ba\left(OH\right)_2\rightarrow Ba\left(HSO_3\right)_2\)

                 2b________b_____________b               (mol)

Ta lập HPT: \(\left\{{}\begin{matrix}a+b=0,15\\a+2b=0,2\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,05\end{matrix}\right.\) 

\(\Rightarrow m_{muối}=m_{BaSO_3}+m_{Ba\left(HSO_3\right)_2}=0,1\cdot217+0,05\cdot299=36,65\left(g\right)\)