Bài 1:
a) \(n_P=\dfrac{12,4}{31}=0,4\left(mol\right)\)
PTHH: \(4P+5O_2\underrightarrow{t^o}2P_2O_5\)
0,4-->0,5--->0,2
\(P_2O_5+3H_2O\rightarrow2H_3PO_4\)
0,2--------------->0,4
\(V_{O_2}=0,5.22,4=11,2\left(l\right)\)
b) \(m_{H_3PO_4}=0,4.98=39,2\left(g\right)\)








