Bài 1:
$\begin{array}{l} PTHH:S+O_2\xrightarrow{t^o} SO_2\\$
$Theo\ pt: \ n_{S}=n_{O_2}=n_{SO_2}=0,2\ mol.\\$
$⇒m_{S}=0,2\times 32=6,4\ g.\\$
$⇒V_{O_2}=0,2\times 22,4=4,48\ lít.\end{array}$
Bài 2:
$\begin{array}{l} PTHH:C+O_2\xrightarrow{t^o} CO_2\\$
$Theo\ pt:\ n_{C}=n_{O_2}=n_{CO_2}=0,18\ mol.\\$
$⇒m_{C}=0,18\times 12=2,16\ g.\\$
$V_{O_2}=0,18\times 22,4=4,032\ l.\end{array}$
Bài 3:
$\begin{array}{l} PTHH:4Al+3O_2\xrightarrow{t^o} 2Al_2O_3\\$
$Theo\ pt:\ n_{Al}=2n_{Al_2O_3}=0,36\ mol.\\$
$⇒m_{Al}=0,36\times 27=9,72\ g.\\$
$Theo\ pt:\ n_{O_2}=\dfrac{3}{2}n_{Al_2O_3}=0,27\ mol.\\$
$⇒V_{O_2}=0,27\times 22,4=6,048\ lít.\end{array}$