Chương IV. Hiđrocacbon. Nhiên liệu

Ta có: \(n_{Br_2}=\dfrac{32}{160}=0,2\left(mol\right)\)

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

Theo PT: \(n_{C_2H_4}=n_{Br_2}=0,2\left(mol\right)\)

\(\Rightarrow V_{C_2H_4}=0,2.22,4=4,48\left(l\right)\)

\(\Rightarrow V_{CH_4}=7,72-4,48=3,24\left(l\right)\)

Sửa đề :thu được \(m_{H_2O}=5,4g\)

Bảo toàn C:\(n_C=n_{CO_2}=\dfrac{13,2}{44}=0,3mol\)

Bảo toàn H:\(n_H=2.n_{H_2O}=2.\dfrac{5,4}{18}=0,6mol\)

\(n_O=\dfrac{9-\left(0,3.12+0,6.1\right)}{16}=0,3mol\)

---> A gồm có C,H và O

\(M_A=30.2=60\) ( g/mol )

Gọi \(CTPT:C_xH_yO_z\)

\(x:y:z=0,3:0,6:0,3=3:6:3\)

\(CTĐG:\left(C_3H_6O_3\right)n=60\)

            \(\Leftrightarrow n=\dfrac{2}{3}\)

\(\rightarrow CTPT:C_2H_4O_2\)

5. 

\(n_X=\dfrac{2,24}{22,4}=0,1mol\\ M_X=2,125.4=8,5g\cdot mol^{^{ }-1}\\ n_{H_2}=a;n_{C_2H_4}=b\\ a+b=0,1\\ 2a+28b=8,5.0,1=0,85\\ a=0,075;b=0,025\\ H_2+C_2H_4-^{^{ }Ni,t^{^{ }0}}->C_2H_6\\ V_{C_2H_6}=0,025.22,4=0,56L;V_{H_2dư}=22,4\left(0,075-0,025\right)=1,12L\)

6. 

Thu được Y chỉ gồm hydrocarbon nên khí hydrogen phản ứng hết.

\(n_A=\dfrac{4,48}{22,4}=0,2mol\\ n_Y=\dfrac{3,36}{22,4}=0,15mol\\ \Delta n_{hh}=n_{H_2\left(pư\right)}=0,05\left(mol\right)\\ n_{C_2H_4}=0,15\left(mol\right)\\ a.\%V_{H_2}=\dfrac{0,05}{0,2}=25\%\\ \%V_{C_2H_4}=75\%\\ b.BTLK\pi:0,15=0,05+n_{Br_2}\\ n_{Br_2}=0,1mol\)

\(a,n_{hh\left(CH_4,C_2H_4,C_2H_2\right)}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\\ n_{CH_4}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\\ n_{hh\left(C_2H_4,C_2H_2\right)}=0,4-0,1=0,3\left(mol\right)\)

Gọi \(\left\{{}\begin{matrix}n_{C_2H_4}=a\left(mol\right)\\n_{C_2H_2}=b\left(mol\right)\end{matrix}\right.\)

=> \(\left\{{}\begin{matrix}a+b=0,3\\28a+26b=8,1\end{matrix}\right.\Leftrightarrow a=b=0,15\left(mol\right)\)

PTHH:

\(CH\equiv CH+2Br-Br\rightarrow CHBr_2-CHBr_2\)

\(CH_2=CH_2+Br-Br\rightarrow CH_2Br-CH_2Br\)

\(b,\left\{{}\begin{matrix}\%V_{CH_4}=\dfrac{0,1}{0,4}.100\%=25\%\\\%V_{C_2H_4}=\%V_{C_2H_2}=\dfrac{0,15}{0,4}.100\%=37,5\%\end{matrix}\right.\)

c, PTHH:

\(CH_4+2O_2\underrightarrow{t^o}CO_2+2H_2O\\ C_2H_2+\dfrac{5}{2}O_2\underrightarrow{t^o}2CO_2+H_2O\\ C_2H_4+3O_2\underrightarrow{t^o}2CO_2+2H_2O\\ Ba\left(OH\right)_2+CO_2\rightarrow BaCO_3\downarrow+H_2O\\ \rightarrow n_{BaCO_3}=n_{CO_2}=0,1+0,15.0,15.2=0,7\left(mol\right)\\ m_{BaCO_3}=0,7.197=137,9\left(g\right)\)

a, C₂H₄ đã pư với dd Brom.

b, Ta có: \(n_{Br_2}=\dfrac{8}{160}=0,05\left(mol\right)\)

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

Theo PT: \(n_{C_2H_4}=n_{Br_2}=0,05\left(mol\right)\Rightarrow m_{C_2H_4}=0,05.28=1,4\left(g\right)\)

4.2 của cậu đeyy:

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

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

Ta có: \(n_{CH_4}+n_{C_2H_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\left(1\right)\)

\(n_{CO_2}=n_{CH_4}+2n_{C_2H_2}=\dfrac{7,84}{22,4}=0,35\left(mol\right)\left(2\right)\)

Từ (1) và (2) \(\Rightarrow\left\{{}\begin{matrix}n_{CH_4}=0,25\left(mol\right)\\n_{C_2H_2}=0,05\left(mol\right)\end{matrix}\right.\)

\(\Rightarrow\left\{{}\begin{matrix}\%V_{CH_4}=\dfrac{0,25.22,4}{6,72}.100\%\approx83,33\%\\\%V_{C_2H_2}\approx16,67\%\end{matrix}\right.\)

Theo PT: \(n_{O_2}=2n_{CH_4}+\dfrac{5}{2}n_{C_2H_2}=0,625\left(mol\right)\Rightarrow m_{O_2}=0,625.32=20\left(g\right)\)

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

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

\(CO_2+Ca\left(OH\right)_2\rightarrow CaCO_{3\downarrow}+H_2O\)

Ta có: \(n_{CaCO_3}=\dfrac{30}{100}=0,3\left(mol\right)\)

Theo PT: \(n_{C_2H_4}=\dfrac{1}{2}n_{CO_2}=\dfrac{1}{2}n_{CaCO_3}=0,15\left(mol\right)\)

\(\Rightarrow V_{C_2H_4}=0,15.22,4=3,36\left(l\right)\)

\(V_{H_2}=5,6-3,36=2,24\left(l\right)\)

Câu `3`

`a)`

`PTHH :`

`C_2H_4+3O_2 ->^{t^o} 2CO_2 + 2H_2O`

`CO_2 + Ca(OH)_2 -> CaCO_3 + H_2O`

`b)`

`n_{C_2H_4} = {14}/{28} = 0,5(mol)`

`n_{O_2} = 3n_{C_2H_4} = 0,5.3 = 1,5(mol)`

`-> V_{O_2} = 1,5.22,4 = 33,6l`

C2H4+3O2-to>2CO2+2H2O

0,5------1,5 mol

n C2H4=0,5 mol

=>VO2=1,5.22,4=33,6l