Question

State True or False.

$KI$ solution is used to identify$A{g}^{+}$.

• A. True
• B. False

Answer 1

The correct option is A True

$A{g}^{+}$give yellow precipitate of silver iodide on reaction with KI solution .

$A{g}^{+}+I^{-}\to AgI\downarrow \stackrel{excessKI}{⟶}$ NO change

yellow ppt

The precipitate is insoluble in dilute or concentrated ammonia but dissolvesin in KCN and in sodium thiosulphate.

$AgI\downarrow +2C{N}^{-}\to \left[Ag\right(CN{)}_2{]}^{-}+I^{-}$

$AgI\downarrow +2S_2{O}_3^{2-}\to \left[Ag\right(S_2{O}_3{)}_2{]}^{3-}+I^{-}$