Question

Potassium iodide (KI) combines with mercury chloride (HgCl2) to form potassium chloride (KCl) and mercury iodide (HgI2) during a double replacement reaction.
Which of the following shows the balanced chemical equation for this reaction?

Answer 1

Answer: The balanced chemical equation is written below.

Explanation:

Double displacement reaction is defined as the chemical reaction in which exchange of ions takes place.

$AB+CD\rightarrow CB+AD$

The chemical equation for the reaction of potassium iodide and mercury (II) chloride follows:

$2KI+HgCl_2\rightarrow HgI_2+2KCl$

By Stoichiometry of the reaction:

2 moles of potassium iodide reacts with mercury (II) chloride to produce 1 mole of mercury (II) iodide and 2 moles of potassium chloride

Hence, the balanced chemical equation is written above.

Answer 2

2Kl+HgCl2 --> 2KCl + HgI2