Among V ( CO )₆, Cr ( CO )₅, Cu ( CO )₃, Mn ( CO )₅, Fe ( CO )₅, [ Co ( CO )₃ ]³⁻, [ Cr ( CO )₄ ]⁴⁻ , and Ir ( CO )₃ , the total number of species isoelectronic with Ni ( CO )₄ is ________. [Given, atomic number: V =23, Cr =24, Mn =25, Fe =26, Co =27, Ni =28, Cu =29, Ir =77 ]

Step-by-step solution

In case of complexes, isoelectronic species should be those having same effective atomic number (EAN) Ni ( CO )₄ 28+4 2=36 (i) V ( CO )₆ 23+2 6=35 (ii) Cr ( CO )₅ 24+2 5=34 (iii) Cu ( CO )₃ 29+2 3=35 (iv) Mn ( CO )₅ 25+2 5=35 (v) Fe ( CO )₅ 26+2 5=36 (vi) [ Co ( CO )₃ ]³⁻ 27+3+2 3=36 (vii) [ Cr ( CO )₄ ]⁴⁻ 24+4+2 4=36 (viii) [ Ir ( CO )₃ ] 77+2 3=83