What are these oxidation numbers?
what are the oxidation number of sulfur in these compounds?
The oxidation number of S are as follows:
Hope this helps :)
You should know that H is usually +1, O is -2, Cl is -1, and Na is +1
So 1: we have -2 from O and 2 times -1 from Cl giving an overall negative charge of -4. Since the compound is neutral, S must have a +4 charge.
Follow the same reasoning for 2-4 and you will have the answer (are you sure you didn't meant H2S for #2?).