C-03-Q165mediumsingle_mcqআয়রনের (Fe, Z=26) ইলেকট্রন বিন্যাস—a1s22s22p63s23p63d64s21s^2 2s^2 2p^6 3s^2 3p^6 3d^6 4s^21s22s22p63s23p63d64s2b1s22s22p63s23p63d81s^2 2s^2 2p^6 3s^2 3p^6 3d^81s22s22p63sc1s22s22p63s23p64s24p61s^2 2s^2 2p^6 3s^2 3p^6 4s^2 4p^61s22s22p63sd1s22s22p63s23p63d74s11s^2 2s^2 2p^6 3s^2 3p^6 3d^7 4s^11s22s22p63s