Q51 · CSIR-NET Chemistry, December 2013
Paper: CSIR-NET December 2013 · Subject: Inorganic Chemistry · Chapter: Coordination Chemistry · Topic: Coordination Chemistry – General · Marks: 2 · Difficulty: Easy
Among the following, the correct combination of complex and its color is
(a)$\left[\mathrm{Co}\left(\mathrm{CN}_{4}\right)\right]^{2-}$ — Red
(b)$\left[\mathrm{Co}\left(\mathrm{Cl}_{4}\right)\right]^{2-}$ — Orange
(c)$\left[\mathrm{Co}(\mathrm{CNS})_{4}\right]^{2-}$ — Blue
(d)$\left[\mathrm{Co}\left(\mathrm{F}_{4}\right)\right]^{2-}$ — Yellow
Answer
Answer: C ✓ checked by 4AB · confidence high
Explanation
Tetrahedral Co(II) thiocyanate, [Co(NCS)₄]²⁻, is the intense blue complex used in the cobalt spot test; [CoCl₄]²⁻ is also blue, not orange.
Study loop for Coordination Chemistry
· Browse this chapter in the app