Đặt `n_{CH_4}=x(mol);n_{C_2H_4}=y(mol);n_{H_2}=z(mol)`

`->x+y+z={3,36}/{22,4}=0,15(1)`

`C_2H_4+Br_2->C_2H_4Br_2`

`->m_{C_2H_4}=m_{\text{bình tăng}}=0,84(g)`

`->28y=0,84`

`->y=0,03(2)`

`M_A={0,975}/{{1,4}/{22,4}}=15,6(g//mol)`

`->m_A=15,6.0,15=2,34=16x+28y+2z(3)`

`(1)(2)(3)->x=0,09(mol);y=z=0,03(mol)`

Vậy trong hỗn hợp đầu:

`V_{H_2}=V_{C_2H_4}=0,03.22,4=0,672(l)`

`V_{CH_4}=0,09.22,4=2,016(l)`

C2H4: 1,7% và CH4:88,3% 

a, Ta có: \(n_{CH_4}+n_{C_2H_4}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\left(1\right)\)

\(16n_{CH_4}+28n_{C_2H_4}=3\left(2\right)\)

Từ (1) và (2) \(\Rightarrow\left\{{}\begin{matrix}n_{CH_4}=0,1\left(mol\right)\\n_{C_2H_4}=0,05\left(mol\right)\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}\%m_{CH_4}=\dfrac{0,1.16}{3}.100\%\approx53,33\%\\\%m_{C_2H_4}\approx46,67\%\end{matrix}\right.\)

- Ở cùng điều kiện nhiệt độ và áp suất, % số mol cũng là %V.

\(\Rightarrow\left\{{}\begin{matrix}\%V_{CH_4}=\dfrac{0,1}{0,15}.100\%\approx66,67\%\\\%V_{C_2H_4}\approx33,33\%\end{matrix}\right.\)

b, PT: \(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)

Có: m _tăng = m_C2H4 = 0,05.28 = 1,4 (g)

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

Gọi \(\left\{{}\begin{matrix}n_{CH_4}=a\left(mol\right)\\n_{C_2H_4}=b\left(mol\right)\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}a+b=0,15\\16a+28b=3\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,05\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}\%V_{CH_4}=\dfrac{0,1}{0,15}.100\%=66,67\%\\\%V_{C_2H_4}=100\%-66,67\%=33,33\%\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}\%m_{CH_4}=\dfrac{0,1.16}{3}.100\%=53,33\%\\\%m_{C_2H_4}=100\%-53,33\%=46,67\%\end{matrix}\right.\)

b) \(m=m_{C_2H_4}=0,05.28=1,4\left(g\right)\)

Đáp án B

Nhận thấy khối lượng bình brom tăng chính là khối lượng ankin và anken hấp thụ

Bảo toàn khối lượng → m_X = m_{bình tăng} + m_Z

→ m_Z = 0,1.26 + 0,2.28 + 0,1.30 + 0,36.2- 1,64= 10,28 gam

\(n_{C_3H_3Ag}=\dfrac{7,35}{147}=0,05\left(mol\right)\)

=> \(n_{C_3H_4}=0,05\left(mol\right)\)

\(n_{Br_2}=\dfrac{6,4}{160}=0,04\left(mol\right)\)

=> \(n_{C_2H_4}=0,04\left(mol\right)\)

=> \(\left\{{}\begin{matrix}\%C_3H_4=\dfrac{0,05.40}{5,52}.100\%=36,23\%\\\%C_2H_4=\dfrac{0,04.28}{5,52}.100\%=20,29\%\\\%C_2H_6=100\%-36,23\%-20,29\%=43,48\%\end{matrix}\right.\)

=> A

a)

$CH_4 + 2O_2 \xrightarrow{t^o} CO_2 + 2H_2O$
$C_2H_4 + 3O_2 \xrightarrow{t^o} 2CO_2 + 2H_2O$

$CO_2 + Ba(OH)_2 \to BaCO_3 + H_2O$

b)

Gọi $n_{CH_4} = a(mol) ; n_{C_2H_4} = b(mol)$
$\Rightarorw a + b = \dfrac{1,68}{22,4} = 0,075(1)$

Theo PTHH : $n_{BaCO_3} = n_{CO_2} = a + 2b = \dfrac{19,7}{197} = 0,1(2)$
Từ (1)(2) suy ra : a = 0,05 ; b = 0,025

$\%V_{CH_4} = \dfrac{0,05}{0,075}.100\% = 66,67\%$

$\%V_{C_2H_4} = 100\% - 66,67\% = 33,33\%$

c) $n_{O_2} = 2n_{CH_4} + 3n_{C_2H_4} = 0,175(mol)$
$\Rightarrow V_{O_2} = 0,175.22,4 = 3,92(lít)$
$\Rightarrow V_{kk} = 5V_{O_2} = 19,6(lít)$