BITSAT2009Chemistryp Block Elements (Group 15, 16, 17 & 18)Actual
Ammonia forms the complex ion [ Cu ( NH ₃ )₄ ]²⁺ with copper ions in alkaline solutions but not in acidic solutions. What is the reason for it?
Options
- AIn acidic solutions protons coordinate with ammonia molecules forming NH ₄⁺ ions and NH ₃ molecules are not av
- BIn alkaline solutions insoluble Cu ( OH )₂ is precipitated which is soluble in excess of any alkali.
- CCopper hydroxide is an amphoteric substance.
- DIn acidic solutions hydration protects copper ions.
Correct answer
A. In acidic solutions protons coordinate with ammonia molecules forming NH ₄⁺ ions and NH ₃ molecules are not av
Step-by-step solution
N H ₃+ H ⁺ (acidic medium) NH ₄⁺