Đặt ``n_{SO_2} = n_{CO_2} = a(mol); n_{CO} = b(mol)`

`n_{hh} = 2a + b (mol)`

`m_{hh} = 64a + 44a + 28b = 108a + 28b (g)`

`M_{hh} = 20,5.2 = 41(g//mol)`

`=> (108a + 28b)//(2a + b) = 41`

`<=> 108a + 28b = 41(2a + b)`

`<=> 26a = 13b`

`=> b = 2a`

`\%V_{CO} = (b)/(2a + b) = (2a)/(2a + 2a) .100\% = 50\%`

`\%V_{CO_2} = \%V_{SO_2} = (100\% - 50\%)/2 = 25\%`

Đặt $n_{hh}$ `=1` mol
$n_{CO}$ `=x` mol , $n_{CO_2}$ `=y` mol , $n_{SO_2}$ `=z` mol
Có hệ pt
$\begin{cases} x+y+z=1\\28x+44y+64z=1.20,5.2\\y-z=0 \end{cases}$
`<=>` $\begin{cases} x=0,5\\y=0,25\\z=0,25 \end{cases}$
`%V`$_{CO}$ `=`$\dfrac{0,5}{1}$ `.100% = 50%`
`%V`$_{CO_2}$ `=`$\dfrac{0,25}{1}$ `.100% = 25%`
`%V`$_{SO_2}$ `=`$\dfrac{0,25}{1}$ `.100% = 25%`