From the stability constant (hypothetical  values)given below, predict which is the strongest ligand?

1. Cu²⁺+4NH₃$\rightleftharpoons$[Cu(NH₃)₄]²⁺;(k=4.5x10¹¹)

2. Cu²⁺+4CN$\rightleftharpoons$[Cu(CN)₄]^2-;(K=2.0x10²⁷)

3. Cu²⁺+2en$\rightleftharpoons$[Cu(en)₂]²⁺;(K=3.0x10¹⁵)

4. Cu²⁺+4H₂O$\rightleftharpoons$[Cu(H₂O)₄]²⁺;(K=9.5x10⁸)

According to IUPAC nomenclature sodium nitroprusside is named as

1. sodium pentacyanonitrosyl ferrate(II)

2. sodium pentacyanonitrosyl ferrate(III)

3. sodium nitroferricyanide

4. sodium nitroferrocyanide

The compound that is not  $\mathrm{\pi }$-bonded organometallic compound is :

1. K[PtCl₃(${\eta }^{\mathit{2}}$-C₂H₄)]

2. Fe(${\eta }^5$-C₅H₅)₂

3. Cr(${\eta }^6$-C₆H₆)₂

4. (CH₃)₄Sn

The complex among the following that exhibits a spin-only magnetic moment of 2.82 B.M. is:

1. Ni(CO)₄

2. [NiCl₄]^2-

3. Ni(PPh₃)₄

4. [Ni(CN)₄]^2-

Atomic number of Cr and Fe are respectively 24 and 26 which of the following is paramagnetic with the spin of electron?

1. [Cr(CO)₆]

2. [Fe(CO)₅]

3. [Fe(CN)₆]^4-

4. [Cr(NH₃)₆]³⁺