Guys, acid rain. Teachers are disagreeing:
2SO2 + O2 ---> 2SO3 (sulphur trioxide)
THEN
SO3 + H2O ---> H2SO4
[OR]
SO2 + H2O ---> H2SO3 (sulphurous acid)
THEN
H2SO3 is oxidised to H2SO4
So, sulphur trioxide intermediate, or sulphurous acid intermediate?