a, \(CH_4+2O_2\underrightarrow{t^o}CO_2+2H_2O\)

\(C_2H_4+3O_2\underrightarrow{t^o}2CO_2+2H_2O\)

\(2C_2H_2+5O_2\underrightarrow{t^o}4CO_2+2H_2O\)

b, Sửa đề: 17,9 (l) → 17,92 (l)

Ta có: \(n_{CO_2}=\dfrac{17,92}{22,4}=0,8\left(mol\right)=n_C\)

\(n_{H_2O}=\dfrac{18}{18}=1\left(mol\right)\Rightarrow n_H=1.2=2\left(mol\right)\)

⇒ m_A = m_C + m_H = 0,8.12 + 2.1 = 11,6 (g)

Theo ĐLBT KL, có: m_A + m_O2 = m_CO2 + m_H2O

⇒ m_O2 = 0,8.44 + 18 - 11,6 = 41,6 (g)

\(\Rightarrow n_{O_2}=\dfrac{41,6}{32}=1,3\left(mol\right)\Rightarrow V_{O_2}=1,3.22,4=29,12\left(l\right)\)

a) PTHH: \(2CO+O_2\underrightarrow{t^o}2CO_2\)  (1)

                \(4H_2+O_2\underrightarrow{t^o}2H_2O\)  (2)

b) Ta có: \(\left\{{}\begin{matrix}\Sigma n_{O_2}=\dfrac{9,6}{32}=0,3\left(mol\right)\\n_{CO_2}=\dfrac{8,8}{44}=0,2\left(mol\right)\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}n_{O_2\left(1\right)}=0,1mol\\n_{O_2\left(2\right)}=0,2mol\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}m_{CO}=0,1\cdot28=2,8\left(g\right)\\m_{H_2}=0,2\cdot2=0,4\left(g\right)\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}\%m_{CO}=\dfrac{2,8}{2,8+0,4}\cdot100\%=87,5\%\\\%m_{H_2}=12,5\%\end{matrix}\right.\)

c) PTHH: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\uparrow\)

Theo PTHH: \(n_{KMnO_4}=2n_{O_2}=0,6mol\)

\(\Rightarrow m_{KMnO_4}=0,6\cdot158=94,8\left(g\right)\)

\(2CO + O_2 \xrightarrow{t^o} 2CO_2\\ 2H_2 + O_2 \xrightarrow{t^o} 2H_2O\\ n_{CO} = n_{CO_2} = \dfrac{8,8}{44} = 0,2(mol)\\ n_{O_2} = \dfrac{n_{CO} + n_{H_2}}{2}=\dfrac{0,2+n_{H_2}}{2} = \dfrac{9,6}{32} = 0,3(mol)\\ \Rightarrow n_{H_2} = 0,4(mol)\\ \%V_{CO} = \dfrac{0,2}{0,2 + 0,4}.100\% = 33,33\%\\ \%V_{H_2} = 100\% - 33,33\% = 66,67\%\\ \%m_{CO} = \dfrac{0,2.28}{0,2.28+0,4.2}.100\%=87,5\%\\ \%m_{H_2} = 100\% - 87,5\% = 12,5\%\)

PTHH: \(C+O_2\xrightarrow[]{t^o}CO_2\)

              a___a______a    (mol)

            \(S+O_2\xrightarrow[]{t^o}SO_2\)

             b___b_______b   (mol)

Ta lập HPT: \(\left\{{}\begin{matrix}12a+32b=10\\a+b=\dfrac{11,2}{22,4}=0,5\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}a=0,3\\b=0,2\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}m_C=0,3\cdot12=3,6\left(g\right)\\m_S=6,4\left(g\right)\\V_{khí}=0,5\cdot22,4=11,2\left(l\right)\end{matrix}\right.\)

\(m_{CH_4} = 8.30\% = 2,4(gam)\\ m_{C_2H_4} = 8 - 2,4 = 5,6(gam)\\ CH_4 + 2O_2 \xrightarrow{t^o} CO_2 + 2H_2O\\ C_2H_4 + 3O_2 \xrightarrow{t^o} 2CO_2 + 2H_2O\\\)

Theo PTHH :

\(n_{CO_2} = n_{CH_4} + 2n_{C_2H_4} = \dfrac{2,4}{16} + \dfrac{5,6}{28}.2 = 0,55(mol)\\ \Rightarrow m_{CO_2} = 0,55.44 = 24,2(gam)\)

\(m_{CH_4}=0.3\cdot8=2.4\left(g\right)\)

\(n_{CH_4}=\dfrac{2.4}{16}=0.15\left(mol\right)\)

\(m_{C_2H_4}=8-2.4=5.6\left(g\right)\)

\(n_{C_2H_4}=\dfrac{5.6}{28}=0.2\left(mol\right)\)

\(CH_4+2O_2\underrightarrow{t^0}CO_2+2H_2O\)

\(C_2H_4+3O_2\underrightarrow{t^0}2CO_2+2H_2O\)

\(n_{CO_2}=2\cdot0.15+0.2=0.5\left(mol\right)\)

\(m_{CO_2}=0.5\cdot44=22\left(g\right)\)

a: \(C+O_2\rightarrow CO_2\)(ĐK: t độ)

x         x          x

\(S+O_2\rightarrow SO_2\)(ĐK: t độ)

y       y         y

b: \(n_{O_2}=\dfrac{11.2}{22.4}=0.5\left(mol\right)\)

Theo đề, ta có hệ:

12x+32y=10 và x+y=0,5

=>x=0,3 và y=0,2

\(m_C=0.3\cdot12=3.6\left(g\right)\)

\(m_S=0.2\cdot32=6.4\left(g\right)\)

c: \(n_{CO_2}=n_C=0.3\left(mol\right)\)

\(n_{SO_2}=n_S=0.2\left(mol\right)\)

\(V_{khí}=22.4\left(0.3+0.2\right)=11.2\left(lít\right)\)

\(n_{O_2}=\dfrac{11,2}{22,4}=0,5\left(mol\right)\)

PTHH :

\(C+O_2\rightarrow\left(t^o\right)CO_2\)

x       x               x 

\(S+O_2\rightarrow\left(t^o\right)SO_2\)

y      y                y

Gọi n C = x 

     n S = y (mol)

Ta có hệ PT :

\(\left\{{}\begin{matrix}12x+32y=10\\x+y=0,5\end{matrix}\right.\)

\(\rightarrow x=0,3;y=0,2\)

\(m_C=0,3.12=3,6\left(g\right)\)

\(m_S=0,2.32=6,4\left(g\right)\)

\(c,V_{hhk}=\left(0,3+0,2\right).22,4=11,2\left(l\right)\)

C₂H₂ + H₂ C₂H₄

C₂H₂ + H₂ C₂H₆

Khi cho hỗn hợp B qua dd nước Br₂ chỉ có C₂H₄ và C₂H₂ phản ứng C₂H₂ +2Br₂ → C₂H₂Br₄

C₂H₄ + Br₂ → C₂H₄Br₂

=> khối lượng bình Br₂ tăng chính bằng khối lượng của C₂H₂ và C₂H₄

m_C2H2 + m_C2H4 = 4,1 (g)    

Hỗn hợp khí D đi ra là CH₄, C₂H₆ và H₂

CH₄ + 2O₂ → t ∘  CO₂ + 2H₂O

C₂H₆ + O₂  → t ∘  2CO₂ + 3H₂O

2H₂ + O₂  → t ∘  2H₂O

Bảo toàn nguyên tố O cho quá trình đốt cháy hh D ta có:

2n_CO2 = 2n_O2 – n_H2O => n_CO2 = ( 0,425. 2– 0,45)/2 = 0,2 (mol)

Bảo toàn khối lượng : m_{hh D} = m_CO2 + m_H2O – m_O2 = 0,2.44 + 0,45.18 – 0,425.32 = 3,3 (g)

Bảo toàn khối lương: m_A = (m_C2H2 + m_C2H4) + m_{hh D} = 4,1 + 3,3 = 7,4 (g)

Đặt \(\left\{{}\begin{matrix}n_{CuO}=x\left(mol\right)\\n_{Fe_2O_3}=y\left(mol\right)\end{matrix}\right.\)

\(m_{CuO}+m_{Fe_2O_3}=40\\ \Rightarrow80x+160y=40\left(1\right)\)

\(PTHH:CuO+H_2\underrightarrow{t^o}Cu+H_2O\\ \left(mol\right)......x\rightarrow.x\\ PTHH:Fe_2O_3+3H_2\underrightarrow{t^o}2Fe+3H_2O\\ \left(mol\right).....y\rightarrow....3y\\ V_{H_2}=\dfrac{13,44}{22,4}=0,6\left(mol\right)\\ \Rightarrow x+3y=0,6\left(2\right)\)

\(\xrightarrow[\left(2\right)]{\left(1\right)}\left\{{}\begin{matrix}80x+160y=40\\x+3y=0,6\end{matrix}\right.\\ \Leftrightarrow\left\{{}\begin{matrix}x=0,3\\y=0,1\end{matrix}\right.\)

a) \(\left\{{}\begin{matrix}m_{CuO}=80.0,3=24\left(g\right)\\m_{Fe_2O_3}=40-24=16\left(g\right)\end{matrix}\right.\)

b) \(\left\{{}\begin{matrix}\%m_{CuO}=\dfrac{24}{40}.100\%=60\%\\\%m_{Fe_2O_3}=100\%-60\%=40\%\end{matrix}\right.\)