NEET2002ChemistryCoordination CompoundsActual
In the silver plating of copper, K [ Ag ( CN ₂ ] . is used instead of AgNO ₃ . The reason is:
Options
- Aa thin layer of Ag is formed on Cu
- Bmore voltage is required
- CAg ⁺ ions are completely removed from solution
- Dless availability of Ag ⁺ ions, as Cu cannot displace Ag from [ Ag ( CN ₂ ]⁻ . ion
Correct answer
D. less availability of Ag ⁺ ions, as Cu cannot displace Ag from [ Ag ( CN ₂ ]⁻ . ion
Step-by-step solution
Copper being more electropositive readily precipitate silver from their salt ( ( Ag ⁺ ) ) solution. ( Cu +2 AgNO ₃ Cu ( NO ₃ )₂+ Ag ) In ( K [ Ag ( CN )₂ ] ) solution a complex anion ( [ Ag ( CN )₂ ] ) is formed so ( Ag ⁺ ) ions are less available in the solution and Cu cannot displace Ag from this complex ion.