$a\big)$

$n_{C_2H_5OH}=\frac{18,4}{46}=0,4(mol)$

$C_2H_5OH+3O_2\xrightarrow{t^o}2CO_2+3H_2O$

Theo PT: $n_{O_2}=3n_{C_2H_5OH}=1,2(mol)$

$\to V_{kk}=1,2.5.22,4=134,4(l)$

$b\big)$

$CO_2+Ca(OH)_2\to CaCO_3\downarrow+H_2O$

Theo PT: $n_{CaCO_3}=n_{CO_2}=2n_{C_2H_5OH}=0,8(mol)$

$\to m_{\downarrow}=m_{CaCO_3}=0,8.100=80(g)$

a, \(n_{C_2H_4}=\dfrac{1,12}{22,4}=0,05\left(mol\right)\)

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

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

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

\(\Rightarrow m_{CaCO_3}=0,1.100=10\left(g\right)\)

b, Theo PT: \(n_{O_2}=3n_{C_2H_4}=0,15\left(mol\right)\Rightarrow V_{O_2}=0,15.22,4=3,36\left(l\right)\)

\(\Rightarrow V_{kk}=\dfrac{V_{O_2}}{20\%}=16,8\left(l\right)\)

\(n_{C_2H_4}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\\ PTHH:C_2H_4+3O_2\rightarrow\left(t^o\right)2CO_2+2H_2O\\ n_{O_2}=3.0,4=1,2\left(mol\right);n_{CO_2}=0,4.2=0,8\left(mol\right)\\ a,V_{O_2\left(đktc\right)}=22,4.1,2=26,88\left(l\right)\\ b,V_{kk\left(đktc\right)}=\dfrac{100}{20}.26,88=134,4\left(l\right)\\ c,CO_2+Ca\left(OH\right)_2\rightarrow CaCO_3\downarrow\left(trắng\right)+H_2O\\ n_{CaCO_3}=n_{CO_2}=0,8\left(mol\right)\\ m_{kết.tủa}=m_{CaCO_3}=100.0,8=80\left(g\right)\)

Ta có: \(\left\{{}\begin{matrix}\overline{M}_{hhkhí}=0,6\cdot29=17,4\\n_{hhkhí}=\dfrac{3,36}{22.4}=0,15\left(mol\right)\end{matrix}\right.\)

Theo phương pháp đường chéo: \(\dfrac{n_{CH_4}}{n_{C_2H_4}}=\dfrac{53}{7}\) \(\Rightarrow\left\{{}\begin{matrix}n_{CH_4}=0,1325\left(mol\right)\\n_{C_2H_4}=0,0175\left(mol\right)\end{matrix}\right.\)

Bảo toàn nguyên tố: \(\Sigma n_{CaCO_3}=n_{CH_4}+2n_{C_2H_4}=0,1675\left(mol\right)\)

\(\Rightarrow m_{CaCO_3}=0,1675\cdot100=16,75\left(g\right)\)

nCO2=8,96/22,4=0,4 mol

=> nC=nCO2=0,4 mol

mC=0,4.12=4,8g

=> mH=5,8-4,8=1g

nH=1 mol -> nH2O=0,5

nH=0,5 mol

Pt: CnH2n+2 + (3n+1/2)O2-> nCO2 + (n+1)H2O

                                                0,4          0,5 mol

=> n/0,4=n+1/0,5 -> n=4

Vậy cthh cần tìm là C4H10

PTHH CH₄+2O₂---t^o--->CO₂+2H₂O

=>\(n_{CH_4}=n_{CO_2}\)

=>Σ\(n_{CO_2}=n_{hh}=\dfrac{11,2}{22,4}=0,5\left(mol\right)\)

PTHH CO₂ +Ca(OH)₂---->CaCO₃ +H₂O

=>\(n_{CaCO_3}=n_{CO_2}=0,5\left(mol\right)\)

=>m_↓=0,5.100=50(g)

Mình nghĩ đề này có vấn đề.

\(n_{C_2H_4}=\dfrac{4.48}{22.4}=0.2\left(mol\right)\)

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

\(0.2.........0.6........0.4..........0.4\)

\(V_{O_2}=0.6\cdot22.4=13.44\left(l\right)\)

\(m_{H_2O}=0.4\cdot18=7.2\left(g\right)\)

\(Ca\left(OH\right)_2+CO_2\rightarrow CaCO_3+H_2O\)

\(..............0.4.....0.4\)

\(m_{CaCO_3}=0.4\cdot100=40\left(g\right)\)

\(n_{CaCO_3}=\dfrac{7,5}{100}=0,075\left(mol\right)\)

=> n_C = 0,075 (mol)

Có \(n_{CO_2}=n_C=0,075\left(mol\right)\)

=> \(n_{H_2O}=\dfrac{4,2-0,075.44}{18}=0,05\left(mol\right)\)

=> n_H = 0,1 (mol)

\(n_{O_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

Bảo toàn O: \(n_{O\left(A\right)}=0,075.2+0,05-0,1.2=0\left(mol\right)\)

=> A chứa C, H

m_A = m_C + m_H = 0,075.12 + 0,1.1 = 1 (g)

\(m_{tăng}=m_{H_2O}+m_{CO_2}=4,2\left(g\right)\\ n_{CaCO_3}=\dfrac{7,5}{100}=0,075\left(mol\right)\)

PTHH: Ca(OH)₂ + CO₂ ---> CaCO₃ + H₂O

                            0,075        0,075

\(\rightarrow m_{CO_2}=0,075.44=3,3\left(g\right)\\ \rightarrow m_{H_2O}=4,2-3,3=0,9\left(g\right)\\ \rightarrow n_{H_2O}=\dfrac{0,9}{18}=0,05\left(mol\right)\\ \rightarrow n_{O\left(sau.pư\right)}=0,05+0,075.2=0,1\left(mol\right)\\ n_{O\left(trong.O_2\right)}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\\ \rightarrow\left\{{}\begin{matrix}n_C=0,075\left(mol\right)\\n_H=0,05.2=0,1\left(mol\right)\\n_O=0,1-0,1=0\left(mol\right)\end{matrix}\right.\)

=> m_A = 0,075.12 + 0,1.1 + 0 = 1 (g)

\(n_{hh}=\dfrac{V_{hh}}{22,4}=\dfrac{1,68}{22,4}=0,075mol\)

Gọi \(\left\{{}\begin{matrix}n_{CH_4}=x\\n_{C_2H_4}=y\end{matrix}\right.\)  \(\Rightarrow\left\{{}\begin{matrix}n_{CO_2\left(CH_4\right)}=x\\n_{CO_2\left(C_2H_4\right)}=2y\end{matrix}\right.\)

\(n_{CaCO_3}=\dfrac{m_{CaCO_3}}{M_{CaCO_3}}=\dfrac{10}{100}=0,1mol\)

\(Ca\left(OH\right)_2+CO_2\rightarrow CaCO_3+H_2O\)

                    x+2y        x+2y             ( mol )

Ta có:

\(\left\{{}\begin{matrix}22,4x+22,4y=1,68\\x+2y=0,1\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x=0,05\\y=0,025\end{matrix}\right.\)

\(\%CH_4=\dfrac{0,05}{0,075}.100=66,66\%\)

\(\%C_2H_4=100\%-66,66\%=33,34\%\)

\(m_{CH_4}=0,05.16=0,8g\)

\(m_{C_2H_4}=0,025.28=0,7g\)

a) \(n_{C_2H_4}=\dfrac{4,958}{24,79}=0,2\left(mol\right)\)

PTHH: \(C_2H_4+3O_2\xrightarrow[]{t^o}2CO_2+2H_2O\)

              0,2---->0,6---->0,4---->0,4

\(\Rightarrow V_{O_2}=0,6.24,79=14,874\left(l\right)\)

b) \(V_{CO_2}=0,4.22,4=9,916\left(l\right)\)

c) \(Ca\left(OH\right)_2+CO_2\rightarrow CaCO_3\downarrow+H_2O\)

                       0,4------>0,4

\(\Rightarrow\left\{{}\begin{matrix}x=m_{CaCO_3}=0,4.100=40\left(g\right)\\y=m_{b\text{ình}.t\text{ăng}}=m_{CO_2}+m_{H_2O}=0,4.44+0,4.18=24,8\left(g\right)\end{matrix}\right.\)