\(n_P=\dfrac{3,1}{31}=0,1\left(mol\right)\\
n_{O_2}=\dfrac{3,2}{32}=0,1\left(mol\right)\\
pthh:4P+5O_2\underrightarrow{t^o}2P_2O_5\\
LTL:\dfrac{0,1}{4}>\dfrac{0,1}{5}\)
P dư
\(n_{P\left(p\text{ư}\right)}=\dfrac{4}{5}n_{O_2}=0,08\left(mol\right)\\
m_{P\left(d\right)}=0,08.31=0,62\left(g\right)\\
n_{P_2O_5}=\dfrac{2}{5}n_{O_2}=0,04\left(mol\right)\\
m_{P_2O_5}=0,04.142=5,68\left(g\right)\\
m_{sp}=0,62+5,68=6,3\left(g\right)\)