CH4+2O2=CO2+2H2O
2H2+O2=2H2O
N2+O2=2NO
2Na+O2=Na2O2
4Ag+O2=2Ag2O
2H2S+O2=2S+2H2O
2H2S+3O2=2SO2+2H2O
6FeO+O2=2Fe3O4
4NH3+5O2=4NO+6H2O
2CH3-COOH+7O2=6CO2+6H2O
N2+3H2=2NH3
280-100%
x-10%
x=(280*10):100=28
M(N2)=28
252:28=x:44.8
x(252*44/8):28=403.2л
<span>2 Fe(OH)2 +7 NaBrO + H2O =2 Fe(OH)3 +5 NaBr + 2NaBrO3
</span><span>3 Zn + KClO3 + 6 KOH + 3 H2O = 3 K2[Zn(OH)4] + KCl
</span><span>
</span>
..............................................
W%=m(элемента)/m(соединения) ×100%
W%=40/56 × 100% = 71.42 %