Question

Ammonia forms the complex ion [Cu(NH₃)₄]²⁺
with copper ions in alkaline solutions but not in
acidic solutions. What is the reason for it ?
(a) In acidic solutions protons coordinate with
ammonia molecules forming NH⁺₄ ions and
NH₃ molecules are not available
(b) In alkaline solutions insoluble Cu(OH)₂ is
precipitated which is soluble in excess of any alkali
(c) Copper hydroxide is an amphoteric substance
(d) In acidic solutions hydration protects copper ions

Answer 1

Answer:

(b) In alkaline solutions insoluble Cu(OH)₂ is

precipitated which is soluble in excess of any alkali

option b