Answer: C
# The main reason why the reaction above can not be balanced is:
This chemical reaction SO2 + H2O -> H2SO2 is not correctly written.
It must be: SO2 + H2O -> H2SO3
Step-by-step explanation:
Note 1:
H2SO2 can be produced by the other chemical reaction:
2H2O + SCl2 -> 2HCl + H2SO2
....
Note 2: Answer A is false
As you can see in the reaction SO2 + H2O -> H2SO3, the oxygen atoms are in two molecules on one side, but one in the other - However, this reaction is written correctly.
Note 3: Answer D is false
Of course the Sulfur atom must be placed in different places: in reactant and product molecules.
Note 4: Answer B is false
There are different kinds of chemical reactions, and this is normal that there are more molecules on one side than on the other.