a. \(n_{O_2}=\dfrac{12.8}{32}=0,4\left(mol\right)\)
\(n_P=\dfrac{50.22}{31}=1,62\left(mol\right)\)
Ta thấy 0,4 < 1,62 => O2 đủ , P dư
PTHH : 4P + 5O2 -> 2P2O5
0,32 0,4 0,16
\(m_{P_2O_5}=0,16.142=22,72\left(g\right)\)
b. \(m_{P\left(dư\right)}=\left(1,62-0,32\right).31=40,3\left(g\right)\)
4P+5O2-to>2P2O5
0,32- 0,4----0,16 mol
n O2=\(\dfrac{12,8}{32}\)=0,4 mol
n P=\(\dfrac{50,22}{31}\)=1,62mol
=>P dư
=>m P2O5=0,16.142=22,72g
=> mP dư=1,3.31=40,3g