\(C_mH_nONa+\left(m+\dfrac{n}{2}-\dfrac{1}{4}\right)O_2\underrightarrow{t^o}\left(m-\dfrac{1}{2}\right)CO_2+\dfrac{n}{2}H_2O+\dfrac{1}{2}Na_2CO_3\)

n_Zn = \(\frac{m}{M}\) = \(\frac{13}{65}\)= 0,2 (mol)

a) PTHH: Zn + H₂SO₄ \(\rightarrow\)ZnSO₄ + H₂

                0,2 -> 0,2       ->     0,2   -> 0,2

b) V_H2 = n . 22,4 = 0,2 . 22,4 = 4,48 (l)

c) m_ZnSO4 = n . M = 0,2 . 161 = 32,2 (g)

d) n_Fe3O4 = \(\frac{m}{M}\) = \(\frac{23,2}{232}\)= 0,1 (mol)

PTHH: 4H₂ + Fe₃O₄ \(\rightarrow\)3Fe + 4H₂O

                         0,1     ->    0,3

m_Fe = n . M = 0,3 . 56 = 16,8 (g)

\(n_{H_2}=\dfrac{4,48}{22,4}=0,2mol\)

\(\left\{{}\begin{matrix}n_{Na}=x\left(mol\right)\\n_{Ba}=y\left(mol\right)\end{matrix}\right.\)

\(2Na+2H_2O\rightarrow2NaOH+H_2\)

\(Ba+2H_2O\rightarrow Ba\left(OH\right)_2+H_2\)

\(\Rightarrow\left\{{}\begin{matrix}0,5x+y=0,2\\23x+137y=18,3\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0,2\\y=0,1\end{matrix}\right.\)

\(\%m_{Na}=\dfrac{0,2\cdot23}{18,3}\cdot100\%=25,14\%\)

Chọn D

\(n_{H_2}=\dfrac{6,72}{22,4}=0,3mol\)

\(2A+6HCl\rightarrow2ACl_3+3H_2\uparrow\)

0,2                                   0,3

Mà \(n_A=\dfrac{m_A}{M_A}\Rightarrow M_A=\dfrac{m_A}{n_A}=\dfrac{7,2}{0,2}=36\)

Không có chất nào thỏa mãn.

Gọi số mol Mg, Cu là a, b (mol)

=> 24a + 64b = 12,2 (1)

\(n_S=\dfrac{1,6}{32}=0,05\left(mol\right)\)

\(n_{SO_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

Mg⁰ - 2e --> Mg⁺²

a---->2a

 Cu⁰ - 2e --> Cu⁺²

b---->2b

S⁺⁶ + 6e --> S⁰

        0,3<-0,05

S⁺⁶ + 2e --> S⁺⁴

         0,3<-0,15

Bảo toàn e: 2a + 2b = 0,6 (2)

(1)(2) => a = 0,175 (mol); b = 0,125 (mol)

=> \(\left\{{}\begin{matrix}m_{Mg}=0,175.24=4,2\left(g\right)\\m_{Cu}=0,125.64=8\left(g\right)\end{matrix}\right.\)

chọn C nhaaaaaaaaaaaaaaaaa

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c 896 m^3 nhé 

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 K đi k đi

Gọi CTHH là \(C_xH_y\).

\(\Rightarrow12x+y=3,17\cdot29\left(1\right)\)

Giả sử có 1 mol X.

\(C_xH_y+\left(x+\dfrac{1}{4}y\right)O_2\underrightarrow{t^o}xCO_2+\dfrac{1}{2}yH_2O\)

1                                        \(x\)            \(\dfrac{1}{2}y\)

\(\dfrac{m_{CO_2}}{m_{H_2O}}=\dfrac{44x}{18\cdot\dfrac{1}{2}y}=4,28\Rightarrow y=1,14x\left(2\right)\)

Từ (1) và (2) \(\Rightarrow\left\{{}\begin{matrix}x=7\\y=8\end{matrix}\right.\Rightarrow C_7H_8\)

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Đáp án C 

\(n_{CH_4}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

Gọi số mol C₂H₄, C₂H₂ là a, b (mol)

=> \(a+b=\dfrac{6,72}{22,4}-0,1=0,2\left(mol\right)\) (1)

\(n_{Br_2}=\dfrac{48}{160}=0,3\left(mol\right)\)

PTHH: C₂H₄ + Br₂ --> C₂H₄Br₂

               a--->a

            C₂H₂ + 2Br₂ --> C₂H₂Br₄

              b---->2b

=> a + 2b = 0,3 (2)

(1)(2) => a = 0,1 (mol); b = 0,1 (mol)

\(\%m_{CH_4}=\dfrac{0,1.16}{0,1.16+0,1.28+0,1.26}.100\%=22,857\%\)

\(\%m_{C_2H_4}=\dfrac{0,1.28}{0,1.16+0,1.28+0,1.26}.100\%=40\%\)

\(\%m_{C_2H_2}=\dfrac{0,1.26}{0,1.16+0,1.28+0,1.26}.100\%=37,143\%\)