\(n_{O_2}=\dfrac{2,8}{22,4}=0,125\left(mol\right)\)
\(n_{H_2}=\dfrac{8,4}{22,4}=0,375\left(mol\right)\)
Ta có phương trình:
2H2 + O2 -to- 2H2O
B.đầu : 0,375.....0,125.......0
P.ứng: 0,25.......0,125.......0,125
Sau p.ứng: 0,125........0...........0,125 (mol)
\(\Rightarrow m_{O_2}=0,25.32=8\left(g\right)\)
Ta có:
\(n_{H_2}=\frac{8,4}{22,4}=0,375\left(mol\right)\\ n_{O_2}=\frac{2,8}{22,4}=0,125\left(mol\right)\)
PTHH: 2H2 + O2 -> 2H2O
Theo PTHH và đề bài, ta có:
\(\frac{0,375}{2}>\frac{0,125}{1}\)
=> O2 hết , H2 dư nên tính theo \(n_{O_2}\)
Ta có:
\(n_{H_2O}=2.0,125=0,25\left(mol\right)\)
=> \(m_{H_2O}=0,25.18=4,5\left(g\right)\)
nO2 = \(\dfrac{2,8}{22,4}=0,125\left(mol\right)\)
nH2 = \(\dfrac{8,4}{22,4}=0,375\left(mol\right)\)
PTHH:
2H2 + O2 - to- 2H2O
B.đầu: 0,375.....0,125.......0
P.ứng: 0,25.........0,125......0,125 (mol)
Sau p.ứng: 0,125.......0............0,125 (mol)
=> mH2O = 0,25.18 = 4,5 (g)