S+H= K+S= SO3+H2O= SO3+KOH= Al+H2SO4=

S+2H=H2S 2K+S=K2S SO3+H2O=H2SO4 SO3+2KOH=K2SO3+H2O 2AL+ 2H2SO4= AL2(SO4)2 +2H2

h2×s=h2s 2k+s=k2s so3+h2o=h2so4 so3+2koh=k2so4+h2o al+6h2so4=al2(so4)3+3so2+6h2o