When a coordination compound CoCl 3 . 6 NH 3 is mixed with AgNO 3 , three moles of AgCl are precipitated per mole of the compound. Write the structural formula and IUPAC name of the coordination compound.

When a coordination compound CoCl 3 . 6 NH 3 is mixed with AgNO 3 moles of AgCl are precipitated per mole of the compound. This indicates that in the coordination compound, all the three chlorine atoms are in the ionisation sphere and six ammonia molecules are in the coordination sphere. Structural formula of the complex is [ Co ( NH 3 ) 6 ] Cl 3 . and IUPAC name of the complex is hexamminecobalt (III) chloride.

Write the IUPAC name of [ Co ( en ) 2 Cl 2 ] + ion and draw the structures of its geometrical isomers.

TheIUPAC name of [ Co ( en ) 2 Cl 2 ] + ion is Dichlorobis(ethyleneamine) cobalt III ion. The structures of geometrical isomers are as shown below, The Trans form does not show optical isomerism but cis form shows optical isomerism.

For the complex ion [ Fe ( CN ) 6 ] 3 - , state the oxidation number of the central metal atom.

Hybridisation is the concept of mixing atomic orbitals to form new hybrid orbitals suitable for describing bonding properties. Electronic configuration of Fe = Ar 4 s 2 3 d 6 Electronic configuration of Fe 3 + = Ar 3 d 5 4 s 0 Hence, the central metal atom contain + 3 oxidation state in its excited state and undergoes d 2 sp 3 hybridisation and the complex has octahedral geometry.

For the complex ion [ Fe ( CN ) 6 ] 3 - , state the magnetic behaviour.

Hybridisation is the concept of mixing atomic orbitals to form new hybrid orbitals suitable for describing bonding properties. Electronic configuration of Fe = Ar 4 s 2 3 d 6 Electronic configuration of Fe 3 + = Ar 3 d 5 4 s 0 Hence, hybridisation is d 2 sp 3 . From the bonding pattern it is observed that this complex contains unpaired electron, so it is paramagnetic in nature.

For the complex ion [ Fe ( CN ) 6 ] 3 - , state the type of hybridisation.

Hybridisation is the concept of mixing atomic orbitals to form new hybrid orbitals suitable for describing bonding properties. Electronic configuration of Fe = Ar 4 s 2 3 d 6 Electronic configuration of Fe 3 + = Ar 3 d 5 4 s 0 Hence, hybridisation is d 2 sp 3 .

Using the valence bond approach, predict the shape, hybridisation and magnetic behaviour of [ Ni ( CO ) 4 ] . (at. no. of Ni = 28 ).

In [ Ni ( CO ) 4 ] , Nickel is in zero valency, i.e., the electronic configuration is [ Ar ] 4 s 2 3 d 8 . The CO is strong field ligand hence two electrons from 4 s transferred to 3 d making it 3 d 10 . The four CO ligands donate electron pairs to the empty 4 s orbital and 4 p orbital giving rise to sp 3 hybrid orbitals. The structure according to literature is tetrahedral which means sp 3 hybridization. All the electrons are paired, so, it is diamagnetic in nature.