\(n_P = \dfrac{3,1}{31} = 0,1(mol)\)
\(4P + 5O_2 \xrightarrow{t^o} 2P_2O_5\)
Theo PTHH :
\(n_{O_2\ pư} = \dfrac{5}{4}n_P =0,125(mol)\\ n_{P_2O_5} = 0,5n_P = 0,05(mol)\)
Vậy :
\(V_{O_2}= 0,125.22,4 = 2,8(lít)\\ m_{P_2O_5} = 0,05.142 = 7,1(gam)\)
PT: \(4P+5O_2\underrightarrow{t^o}2P_2O_5\)
Ta có: \(n_P=\dfrac{3,1}{31}=0,1\left(mol\right)\)
\(n_{O_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)
Xét tỉ lệ: \(\dfrac{0,1}{4}< \dfrac{0,3}{5}\), ta được O2 dư.
Theo PT: \(\left\{{}\begin{matrix}n_{O_2\left(pư\right)}=\dfrac{5}{4}n_P=0,125\left(mol\right)\\n_{P_2O_5}=\dfrac{1}{2}n_P=0,05\left(mol\right)\end{matrix}\right.\)
\(\Rightarrow V_{O_2\left(pư\right)}=0,125.22,4=2,8\left(l\right)\)
\(m_{P_2O_5}=0,05.142=7,1\left(g\right)\)
Bạn tham khảo nhé!