[imperius]

Compose the balanced reaction equation for the following reaction occuring in acidic aqueous medium.
Reduce all coefficients to the lowest possible integral values.
Include H2O(l) and H+(aq) appropriately to complete the equation.

As2S3(s) + NO3−(aq) → H3AsO4(aq) + NO(g) + S8(s)

Problems:
1. What are the individual oxidation states for As2S3?
2. How do you find the half reactions?

[Borek]

S in sulfides - always -2.

I would go for half reactions method (ignoring oxidation numbers)

http://www.chembuddy.com/?left=balancing-stoichiometry&right=half-reactions-method

With these half reactions:

As₂S₃(s) → H₃AsO₄(aq) + S₈(s)

NO₃⁻(aq) → NO(g)