Given below are two statements : Statement I : Among . [ Cu ( NH ₃ )₄ ]²⁺, [ Ni ( en )₃ ) ]²⁺, [ Ni ( NH ₃ )₆ ]²⁺ and [ Mn ( H ₂ O )₆ ]²⁺ , [ Mn ( H ₂ O )₆ ]²⁺ has the maximum number of unpaired electrons. Statement II : The number of pairs among [ NiCl ₄ ]²⁻, [ Ni ( CO )₄ ] , [ NiCl ₄ ]²⁻, [ Ni ( CN )₄ ]²⁻ and [ Ni ( CO )₄ ], [ Ni ( CN )₄ ]²⁻ that contain only diamagnetic species is two. In the light of the above st

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Statement I: Unpaired electrons in each complex: [Cu(NH₃)₄]²⁺ : Cu²⁺ is d^9 → 1 unpaired [Ni(en)₃]²⁺ : Ni²⁺ is d^8 , octahedral → 2 unpaired [Ni(NH₃)₆]²⁺ : Ni²⁺ is d^8 → 2 unpaired [Mn(H₂O)₆]²⁺ : Mn²⁺ is d^5 , weak field → high spin → 5 unpaired [Mn(H₂O)₆]²⁺ has maximum. Statement I is true. Statement II: [NiCl₄]²⁻ : Ni²⁺ ( d^8 ), tetrahedral → paramagnetic [Ni(CO)₄] : Ni^0 ( d¹⁰ ) → diamagnetic [Ni(CN)₄]²⁻ : Ni²⁺ ( d^8 ), square planar → diamagnetic Only pair [Ni(CO)₄], [Ni(CN)₄]²⁻ has both diamagnetic. Count = 1,