the anseqr will be (d) it will be easy if you know the reaction Mn(2+) in acidic medium
MnO4(-1) +8H(+) +5 Fe(2+)---------Mn(2+) +5Fe3+ +4H2O
clearly 5 mole of iron react with 1 mole of mno4-
therefore10×.1=1millimole of iron will react with 1/5×1=.2millimole
thNks and regards
sunil kumar
askIItian faculty