CUET · CHEMISTRY · PYQ PAPER 2025
Select the high spin complexes from the following:
(A) \(\left[ Ni ( CN )_4\right]^{2-}\)
(B) \(\left[ Fe ( CN )_6\right]^{3-}\)
(C) \(\left[ MnBr _4\right]^{2-}\)
(D) \(\left[ Fe \left( H _2 O \right)_6\right]^{2+}\)
Choose the correct answer from the options given below:
- A (B) and (C) only
- B (C) and (D) only
- C (A) and (D) only
- D (A) and (B) only
Answer & Solution
Correct Answer
(B) (C) and (D) only
Step-by-step Solution
Detailed explanation
(A) \(\left[ Ni ( CN )_4\right]^{2-}\): \(\text{Ni}^{2+}\) (\(d^8\)), \(\text{CN}^-\) (strong field), square planar \(\rightarrow\) Low spin. (B) \(\left[ Fe ( CN )_6\right]^{3-}\): \(\text{Fe}^{3+}\) (\(d^5\)), \(\text{CN}^-\) (strong field), octahedral \(\rightarrow\) Low…
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