Total number of molecules/species from the following which will be paramagnetic is ________________________.
\[
O_2, O_2^+, O_2^-, NO, NO_2, CO, K_2[NiCl_4], [Co(NH_3)_6]Cl_3, K_2[Ni(CN)_4]
\]
Show Hint
Correct Answer: 5
Solution and Explanation
A species is paramagnetic if it has unpaired electrons:
- \( O_2 \) (paramagnetic) ✅
- \( O_2^+ \) (paramagnetic) ✅
- \( O_2^- \) (paramagnetic) ✅
- \( NO \) (paramagnetic) ✅
- \( NO_2 \) (paramagnetic) ✅
- \( CO \) (diamagnetic) ❌
- \( [Co(NH_3)_6]Cl_3 \) (diamagnetic) ❌
- \( K_2[Ni(CN)_4] \) (diamagnetic) ❌
Total paramagnetic species = 5.
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