Problem- Which reagent can affect the following transformation? I think a and b can do the same thing although I'm not sure why one nitro group reduces down to nh2 and not both nitro groups in the transformation.
1, 4-dinitro benzene transformed into 4-nitroaniline
a) Fe/HCl; then OH- b) H2S, NH3, C2H5OH c) H2,Ni, High Pressure d) Zn(Hg)/HCl e) Raney Ni
I am in urgent need of solution of above problem with complete explanation