The order of increasing CO stretching frequencies in [Co(CO)₄]⁻, [Cu(CO)₄]⁺, [Fe(CO)₄]²⁻ and [Ni(CO)₄] is

Question

Accepted Answer

(b) [Fe(CO)₄]²⁻< [Co(CO)₄]⁻< [Ni(CO)₄]< [Cu(CO)₄]⁺. Explanation: ν(CO) rises as negative charge falls: [Fe(CO)₄]²⁻ < [Co(CO)₄]⁻ < Ni(CO)₄ < [Cu(CO)₄]⁺ (b).

Answer

(a) [Cu(CO)₄]⁺< [Ni(CO)₄]< [Co(CO)₄]⁻< [Fe(CO)₄]²⁻

Answer

(c) [Co(CO)₄]⁻< [Fe(CO)₄]²⁻< [Cu(CO)₄]⁺< [Ni(CO)₄]

Answer

(d) [Ni(CO)₄]< [Cu(CO)₄]⁺< [Co(CO)₄]⁻< [Fe(CO)₄]²⁻

The order of increasing CO stretching frequencies in [Co(CO)₄]⁻, [Cu(CO)₄]⁺, [Fe(CO)₄]²⁻ and [Ni(CO)₄] is · ABC26IN0774