Question

When the solution of substance 'X' added to potassium lodide, than a yellow solid separated out from the solution. The substance X could be ______

• A. $Pb{I}_2$
• B. $Pb(N{O}_3{)}_2$
• C. $NaI$
• D. All

Answer 1

The correct option is B $Pb(N{O}_3{)}_2$

• Substance $X$ is likely to be Lead Nitrate ($Pb(N{O}_3{)}_2$.)
• a yellow precipitate is formed during the reaction and it is called lead iodide.
  
• it is an example of a double displacement reaction.
  
• it is characterized by the formation of a precipitate
  
• The complete balanced chemical reaction is
  

• $2KI+Pb(N{O}_3{)}_2\to 2KN{O}_3+\underset{\text{yellow precipitate}}{Pb{I}_2}$

Hence, option A is correct.