Question

Chlorine gas is passed in an aqueous potassium iodide solution to form potassium chloride solution and solid iodine. Identify the type of the reaction:

• A. Decompostion reaction
• B. Double Displacement reaction
• C. Displacement reaction
• D. None of these

Answer 1

Answer: (C)

Displacement reaction

When chlorine ($C{l}_2$) gas is passed through an aqueous solution of potassium iodide ($KI$), the products formed are solid iodine ($I_2$) and potassium chloride ($KCl$). This is a displacement reaction in which the less reactive iodine in potassium iodide is displaced by the more reactive chlorine. The equation can be written as:
$2KI\left(aq\right)+C{l}_2\left(g\right)\to 2KCl\left(aq\right)+I_2\left(s\right)$