4Na+O2->2Na2O: Natri oxit
2Mg+O2->2MgO: Magie oxit
2Cu+O2->2CuO: Đồng oxit
S+O2->SO2: Lưu huỳnh đi oxit
4Al+3O2->2Al2O3: Nhôm oxit
C+O2->CO2: Cacbon đi oxit
N+O2->NO2: nito oxit
4P+5O2->2P2O5: đi phot pho pentaoxit
Oxit axit oxit bazo
SO2 Na2O
CO2 MgO
NO2 CuO
P2O5 Al2O3
2.
nP=6.2/31=0.2mol
nO2=6.72/22.4=0.3mol
PTPU:
4P+5O2->2P2O5
Xét 0.2/4<0.3/5
=> P hết, O2 dư
=> tính theo nP
nO2=5/4nP=5/4*0.2=0.25mol
nO2 dư=0.3-0.25=0.05mol
=>mO2 dư=0.05*32=1.6gam
b. Theo PT ta có: nP2O4=nP=0.2mol
=>mP2O5=0.2*142=28.4gam
3. 3Fe + 2O2 -> Fe3O4
a. nFe3O4=2.32/232=0.1mol
Theo PT ta có: nFe=3nFe3O4=0.3mol
nO2=2nFe3O4=0.2mol
=>mFe=0.3*56=1608gam
=>vO2=0.2*22.4=4.48lit
b. 2KMnO4 -> K2MnO4 + MnO2 + O2
Theo PT ta có: nKMnO4=2nO2=0.4mol
=>mKMnO4=0.4*158=63.2gam