Match the colour of precipitate listed in column-I with the reagent(s) listed in column II.
`{:(Column-I,Column-II),((A)Bi^(3+)"gives black precipitate with",(p)"Saturated solution of " H_2S " in water"),((B)Cu^(2+)"gives black precipitate with",(q)"Potassium thiocyanate soluion"),((C )Zn^(2+)"gives white precipitate with",(r)"Potassium iodide solution"),((D)Ag^+"gives white precipitate with",(s)"Potassium ferrocyanide solution"),(,""):}`

Explanation

To solve the problem of matching the colors of precipitates from Column-I with the reagents from Column-II, we will analyze each cation and the corresponding precipitate it forms with the given reagents.

### Step-by-Step Solution:

1. **Identify the Reaction for Bi³⁺ (Bismuth ion)**:
- Bi³⁺ reacts with H₂S to form Bi₂S₃, which is a **black precipitate**.
- Therefore, **(A) Bi³⁺ gives black precipitate with (p) Saturated solution of H₂S in water**.

**Match**: A → P

2. **Identify the Reaction for Cu²⁺ (Copper ion)**:
- Cu²⁺ reacts with H₂S to form CuS, which is also a **black precipitate**.
- Cu²⁺ reacts with potassium thiocyanate (KSCN) to form Cu(SCN)₂, which initially is a **black precipitate** but can change to white upon standing.
- Therefore, **(B) Cu²⁺ gives black precipitate with (p) Saturated solution of H₂S in water and (q) Potassium thiocyanate solution**.

**Match**: B → P, Q

3. **Identify the Reaction for Zn²⁺ (Zinc ion)**:
- Zn²⁺ reacts with H₂S to form ZnS, which is a **white precipitate**.
- Zn²⁺ reacts with potassium ferrocyanide to form K₂Zn₃[Fe(CN)₆]₂, which is also a **white precipitate**.
- Zn²⁺ does not form a precipitate with potassium iodide as ZnI₂ is soluble.
- Therefore, **(C) Zn²⁺ gives white precipitate with (p) Saturated solution of H₂S in water and (s) Potassium ferrocyanide solution**.

**Match**: C → P, S

4. **Identify the Reaction for Ag⁺ (Silver ion)**:
- Ag⁺ reacts with potassium ferrocyanide to form Ag₄[Fe(CN)₆], which is a **white precipitate**.
- Ag⁺ reacts with potassium thiocyanate to form AgSCN, which is also a **white precipitate**.
- Ag⁺ does not form a precipitate with H₂S as it forms Ag₂S, which is a **black precipitate**, and with potassium iodide, it forms AgI, which is a **yellow precipitate**.
- Therefore, **(D) Ag⁺ gives white precipitate with (q) Potassium thiocyanate solution and (s) Potassium ferrocyanide solution**.

**Match**: D → Q, S

### Summary of Matches:
- A → P
- B → P, Q
- C → P, S
- D → Q, S

### Final Matches:
- (A) Bi³⁺ → (p) H₂S
- (B) Cu²⁺ → (p) H₂S, (q) KSCN
- (C) Zn²⁺ → (p) H₂S, (s) K₃[Fe(CN)₆]
- (D) Ag⁺ → (q) KSCN, (s) K₃[Fe(CN)₆]