# Which name-formula combination is NOT correct?

$\begin{array}{1 1}(a)\;FORMULA:[Co(NH_3)_4(OH_2)I]SO_4,NAME:\text{tetraammineaquaiodocobalt(III) sulfate}\\(b)\;FORMULA:K[Cr(NH_3)_2Cl_4],NAME:\text{potassium diamminetetrachlorochromate(III)}\\(c)\;FORMULA:[Mn(CN)_5]^{2-},NAME:\text{pentacyanomanganate(II) ion}\\(d)\;FORMULA:[Ni(CO)_4],NAME:\text{tetracarbonylnickel(0)}\end{array}$

FORMULA:$[Mn(CN)_5]^{2-}$,NAME:$\text{pentacyanomanganate(II) ion}$
Hence (c) is the correct answer.