Ok so this is the equation:
As2S3(s) + NO3-(aq) ® H3AsO4(aq) + NO(g) + S8(s)
and I've tried to split it into 2 half reactions:
i) NO3^-(aq) -> NO(g)
NO3-(aq) + 4H^+(aq) -> NO(g) + 2H2O(l)
3e^- + NO3^-(aq) +4H^+(aq) -> NO(g) + 2H2O(l)
ii) As2S3(s) -> H3AsO4(aq) + S8(s)
but I can't balance this one - where did I go wrong?