Coordination Compounds

The d-electron configurations of Cr2+, Mn2+, Fe2+ and Co2+ are d4, d5, d6 and d7 respectively. Which one of the following will exhibit minimum paramagnetic behaviour? (At. Nos. Cr = 24, Mn = 25, Fe = 26, Co = 27)

1. [Mn(H2O)6]2+
2. [Fe(H2O)6]2+
3. [Co(H2O)6]2+
4. [Cr(H2O)6]2+

Which of the following carbonyls will have the strongest C–O bond?

1. Mn(CO)6+
2. Cr(CO)6
3. V(CO)6-
4. Fe(CO)5

Which of the following complex compounds will exhibit highest paramagnetic behaviour?

1. [Ti(NH3)6]3+
2. [Cr(NH3)6]3+
3. [Co(NH3)6]3+
4. [Zn(NH3)6]2+

Which of the following complex ions is not expected to absorb visible light?

1. [Ni(CN)4]2-
2. [Cr(NH3)6]3+
3. [Fe(H2O)6]2+
4. [Ni(H2O)6]2+

Crystal field stabilization energy for high spin d4 octahedral complex is

1. -1.8 0
2. -1.6 0 + P
3. -1.2 0
4. -0.6 0

The existence of two different coloured complexes with the composition of [Co(NH3)4Cl2]+ is due to

1. linkage isomerism
2. geometrical isomerism
3. coordination isomerism
4. ionization isomerism.

Which one of the following complexes is not expected to exhibit isomerism?

1. [Ni(NH3)4(H2O)2]2+
2. [Pt(NH3)2Cl2]
3. [Ni(NH3)2Cl2]
4. [Ni(en)3]2+

Which of the following does not show optical isomerism? (en = ethylenediamine)

1. [Co(NH3)3Cl3]0
2. [Co(en)Cl2(NH3)2]+
3. [Co(en)3]3+
4. [Co(en)2Cl2]+

Which of the following complex ions is expected to absorb visible light? (At. nos. Zn = 30, Sc = 21, Ti = 22, Cr = 24)

1. [Ti(en)2(NH3)2]4+
2. [Cr(NH3)6]3+
3. [Zn(NH3)6]2+
4. [Sc(H2O)3(NH3)3]3+

Which of the following complexes exhibits the highest paramagnetic behaviour? where gly = glycine, en = ethylenediamine and bpy = bipyridyl moieties. (At. nos. Ti = 22, V = 23, Fe = 26, Co = 27)

1. [Co(ox)2(OH)2]-
2. [Ti(NH3)6]3+
3. [V(gly)2(OH)2(NH3)2]+
4. [Fe(en)(bpy)(NH3)2]2+