Sample EP 6 problem explained

Sb+HNO3-->Sb2O5+NO +H2O


sb=0
H=+1, N=+5, 0=(-2) 3


sb2O5=sb=+5, O=(-2)5
N=+2 O=-2

H=+1, O=-2

Sb 0--> +5 loss of electron oxidation, reducing agent
N=+5-->+2 gain electrons reduction, oxidizing agent