28  NO3−  + 3As2S3 +  4H2O →   6AsO43−+28NO+9SO42−+8H+.What will be the equivalent mass of As2S3 in above reaction : (Molecular mass of As2S3 = M)?

From the given equation ,                                  As+32S-23→As+5O4-3 + S+6O4-2 Change in oxidation state of  ‘As’  = 2(2) =4 Change in oxidation state of  ‘S’ = 3(8) = 24Total change in oxidation state = n-factor = 24+4=28∴ Equivalent weight of As2S3 = M28Where M= molecular mass