Question

Which of the following option is incorrect ?

• A. $\left[\right(N{H}_3{)}_{5}Co-OH-Co\left(N{H}_3{)}_5\right]C{l}_5$ : Pentaammine cobalt(III) – $\mu$ – hydridopentaamminecobalt(III) chloride
• B. $\left[Cr\right(en{)}_3\left]\right[Ni\left(CN{)}_5{H}_{2}O\right]$ : Triethylenediammine chromium(III) aquapentacyanidonickelate(II)
• C. $K_2\left[OsC{l}_{5}N\right]$ : Potassium pentachloridonitridoosmate (VI)
• D. $\left[Fe\right(C_5{H}_5{)}_2]$ : Bis(cyclopentadienyl) iron (II)

Answer 1

The correct option is B $\left[Cr\right(en{)}_3\left]\right[Ni\left(CN{)}_5{H}_{2}O\right]$ : Triethylenediammine chromium(III) aquapentacyanidonickelate(II)

We should be able to tell right away that option (b) is incorrect because there are three $en$ groups and if multiple $en$ groups need to be named with a bis or a tris but here its given as tri!
The correct name of this compound would be Tris(ethylenediammine) chromium(III) aquapentacyanidonickelate(II).