`2KCN+Pb(NO_(3))_(2) to Pb(CN)_(2)darr+2KNO_(3)`

Options

A. For coloured ppt./Black ppt
B. For coloured solution.
C. for clear/colourless solution
D. For white ppt.

Answer

To solve the question regarding the reaction \( 2KCN + Pb(NO_3)_2 \rightarrow Pb(CN)_2 + 2KNO_3 \), we need to analyze the products formed and their characteristics. Here’s a step-by-step breakdown:

### Step 1: Identify the Reactants
The reactants in the reaction are:
- \( KCN \) (Potassium cyanide)
- \( Pb(NO_3)_2 \) (Lead(II) nitrate)

### Step 2: Write the Balanced Reaction
The balanced chemical equation is:
\[ 2KCN + Pb(NO_3)_2 \rightarrow Pb(CN)_2 + 2KNO_3 \]

### Step 3: Identify the Products
The products of the reaction are:
- \( Pb(CN)_2 \) (Lead(II) cyanide)
- \( KNO_3 \) (Potassium nitrate)

### Step 4: Determine the Nature of the Products
Now we need to analyze the characteristics of the products:
- **Lead(II) cyanide (\( Pb(CN)_2 \))**: This compound is known to be a white precipitate.
- **Potassium nitrate (\( KNO_3 \))**: This is a soluble salt and does not contribute to the color of the solution.

### Step 5: Conclusion on the Appearance of the Reaction
Since \( Pb(CN)_2 \) is a white precipitate, we conclude that the reaction will form a white precipitate. Therefore, the correct answer is option D, which states that the reaction forms a white precipitate.

### Summary of the Solution
The reaction \( 2KCN + Pb(NO_3)_2 \) produces \( Pb(CN)_2 \) as a white precipitate along with \( 2KNO_3 \). Thus, the answer is that the reaction forms a white precipitate.

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