Question

Primary and secondary valency of Pt in [Pt(NH3)6]CI4, is
(1) 4, 4
(2) 4,6
(3) 6,6
(4) 3,4​

Answer 1

The correct option is 2.

• The primary valency of any coordination compound is its charge.
• The charge of $[Pt(NH_3)_6]Cl_4$ is +4 so, its primary valency will be 4.
• Again secondary valency of any coordination compound is defined as the number of ligands attached to the metal.
• Here six amino groups are attached to the Pt metal so, the secondary valency will be 6.
• The primary and secondary valency of Pt in $[Pt(NH_3)_6]Cl_4$ is 4,6.

Answer 2

Answer: (2) 4,6

Explanation:

[Pt(NH3)6]CI4

Here let  primary valence i.e valency of Pt (metal) be x

Valency of Nh3 is 0 so valency of (NH3)6 = 6 x 0

Valency of Cl is -1 so valency of (Cl4) = 4 x -1

Now since sum of all the valencies is 0 i.e

x + 6(0) + 4(-1) = 0

x = + 4

Primary valence is  +4

Now here here we have 1 monoligands i.e (Nh3)  having 6 atom

so Secondary valence is 6

Correct Answer : (2) 4,6