a,
\(n_P=\frac{9,3}{31}=0,3\left(mol\right)\)
\(PTHH:4P+5O_2\rightarrow2P_2O_5\)
_______0,3______0,375____________(mol)
\(\Rightarrow V_{O2}=0,375.22,4=8,4\left(l\right)\)
b,
\(2KClO_3\underrightarrow{^{to}}2KCl+3O_2\uparrow\)
025________________0,375
\(\Rightarrow m_{KClO3}=0,25.122,5=30,625\left(g\right)\)