Đốt cháy hoàn toàn 20,0 ml hỗn hợp X gồm C3H6, CH4, CO

\(20 \ ml \left\{\begin{matrix} C_{3}H_{6} \ \\ CH_{4} \ \ \\ CO \ \ \end{matrix}\right. \Rightarrow 24 \ ml \left\{\begin{matrix} 3CO_{2 } \\ CO_{2} \ \\ CO_{2} \ \end{matrix}\right. , \ \Delta V = 2V_{C_{3}H_{6}}\)
\(\\ \Rightarrow V_{C_{3}H_{6}} = \frac{24-20}{2} = 2 \ ml \\ V_{CO}=2V_{CH_{4}}; \ V_{CO} + V_{CH_{4}} = 20-2 = 18 \ ml \\ \Rightarrow V_{CH_{4}} = 6 \ ml; \ V_{CO} = 12 \ ml\)
\(\\ \overline{M}_{X} = \frac{42.2 + 16.6 + 28.12}{20} = 25,8 \\ \Rightarrow d_{\frac{X}{H_{2}}} = \frac{25,8}{2} = 12,9\)