NTA Abhyas JEE Main2020ChemistryCoordination CompoundsPractice
Ammonia forms the complex [ C u ( N H 3 ) 4 ] 2 + with copper ions in alkaline solution but not in acidic solution. The reason for this is
Options
- AIn alkaline solution C u ( O H ) 2 is precipitated which is soluble in excess of alkali
- BCopper hydroxide is amphoteric substance
- CIn acidic solution hydration protects C u 2 + ions
- DIn acidic solution protons are coordinated with ammonia molecules forming N H 4 + ions
Correct answer
D. In acidic solution protons are coordinated with ammonia molecules forming N H 4 + ions
Step-by-step solution
Ammonia forms the complex C u N H 3 4 2 + with copper ions in alkaline solution but not in acidic solution. The reason for this is In acidic solution protons are coordinated with ammonia molecules forming N H 4 + ions. C u 2 + a q + 4 N H 3 → C u N H 3 4 2 + Cu 2+   +   4NH 4 + → No   complex   formation