B

b

B

  D. 42,67 lít 

D

D

nCH4 = 4,48/22,4 = 0,2 (mol)

PTHH: CH4 + 2O2 -> (t°) CO2 + 2H2O

Mol: 0,2 ---> 0,4

Vkk = 0,4 . 22,4 : 21% = 128/3 (l)

44,8(l)

44,8 \(l\)

CH4+2O2-to>CO2+2H2O

0,5-----1 mol

n CH4=\(\dfrac{11,2}{22,4}\)=0,5 mol

=>Vkk=1.22,4.5=112l

a) \(n_{C_2H_4}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

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

           0,3---->0,9------>0,6

\(\Rightarrow V_{kk}=\dfrac{0,9.22,4}{20\%}=100,8\left(l\right)\)

b) \(V_{CO_2}=0,6.22,4=13,44\left(l\right)\)

c) \(n_P=\dfrac{15,5}{31}=0,5\left(mol\right)\)

PTHH: \(4P+5O_2\xrightarrow[]{t^o}2P_2O_5\)

Xét tỉ lệ: \(\dfrac{0,5}{4}< \dfrac{0,9}{5}\Rightarrow\) O₂ dư, P cháy hết

\(n_{hh}=\dfrac{11.2}{22.4}=0.5\left(mol\right)\)

\(n_{CH_4}=a\left(mol\right),n_{H_2}=b\left(mol\right)\)

\(\Rightarrow a+b=0.5\left(1\right)\)

\(n_{H_2O}=2a+b=\dfrac{12.6}{18}=0.7\left(mol\right)\left(2\right)\)

\(\left(1\right),\left(2\right):a=0.2,b=0.3\)

\(n_{CO_2}=n_{CH_4}=0.2\left(mol\right)\)

\(V=0.2\cdot22.4=4.48\left(l\right)\)

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

PT: \(CH_4+2O_2\underrightarrow{t^o}CO_2+2H_2O\)

Theo PT: \(n_{O_2}=2n_{CH_4}=0,2\left(mol\right)\Rightarrow V_{O_2}=0,2.22,4=4,48\left(l\right)\)

\(\Rightarrow V_{kk}=\dfrac{V_{O_2}}{20\%}=22,4\left(l\right)\)

\(CH_4+2O_2\rightarrow\left(t^o\right)CO_2+2H_2O\\ n_{CH_4}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\\ n_{CO_2}=n_{CH_4}=0,2\left(mol\right)\\ n_{O_2}=2.n_{CH_4}=2.0,2=0,4\left(mol\right)\\ a,V_{kk}=5.V_{O_2\left(đktc\right)}=5.\left(0,4.22,4\right)=44,8\left(l\right)\\ b,m_{CO_2}=0,2.44=8,8\left(g\right)\)

\(2H_2+O_2\rightarrow\left(t^o\right)2H_2O\\ n_{O_2}=\dfrac{n_{H_2}}{2}\Rightarrow V_{O_2\left(đktc\right)}=\dfrac{V_{H_{2\left(đktc\right)}}}{2}=\dfrac{2,24}{2}=1,12\left(l\right)\\ Chọn.A\)