Distillation

Froth floatation

Cupellation

Treatment of KCN

Ni

H₂SO₄

NH₃

HNO₃

[Co(en)(NH₃)₂Cl₂]Cl

[Co(en)₂Cl₂]Cl

[Co(NH₃)₂−Cl₃]

[Co(en)₃]Cl₃

Cu²⁺ is hydrated in acidic medium

Cu(OH)₂ is formed in alkaline solution which dissolves in NH₃ (excess)

NH₃ is protonated to form NH₄⁺ in acidic medium, therefore, pair of electrons is no more available for coordination

Cu(OH)₂ is amphoteric

Ni is dsp² hybridised

Tetrahedral shape

Low spin complex

All of these