Match the entries of column I with appropriate entries of column II and choose the correct option out of the four options given.
| Column I (ion) | Column II (E.C.) |
| (a) Mn2+ | (i) [Ar]3d6 |
| (b) Cu+ | (ii) [Ar] |
| (c) Sc3+ | (iii) [Ar]3d10 |
| (d) Fe2+ | (iv) [Ar]3d5 |
Answer & explanation
Correct answer: option 3
25Mn: [Ar]4s23d5
(a) Mn2+ : [Ar]3d5
29Cu: [Ar]4s13d10
(b) Cu+ : [Ar]3d10
21Sc: [Ar]4s23d1
(c) Sc3+ : [Ar]
26Fe: [Ar]4s23d6
(d) Fe2+ : [Ar]3d6